A randomized trial of nortriptyline for smoking cessation

Drug delivery strategies for the treatment of relapse behavior in substance use disorder- A systematic review

Substance use disorders (SUDs) pose a significant global health challenge, with relapse being a major obstacle in achieving successful treatment outcomes. In recent years, drug delivery strategies have emerged as promising tools to improve treatment efficacy and patient compliance in the context of SUD. Here we explore a diverse range of drug delivery strategies that have been investigated for addressing relapse behavior in SUD. By examining a wide array of clinical and preclinical studies, this review highlights the advances made in drug delivery technologies in the hopes of aiding future research to further establish novel systems. The present systematic review has been created after gathering data from multiple databases including Google Scholar, PubMed and Cochrane, taking into account both review and research (preclinical and clinical) studies along with other systematic reviews and meta-analyses. Relevant articles have been categorized into those pertaining to opioid use disorder, alcohol use disorder and tobacco use disorder. Substance use disorders are a global health problem, with tobacco use associated with the highest mortality, followed by alcohol and opioids. Conventional drug delivery options, such as oral medication have a number of disadvantages, such as low compliance. To tackle these challenges, multiple novel strategies such as sustained release implants, transdermal patches and liquid crystal-based injections have been developed. This systematic review presents a concise view of the strategies already available, as well as those currently undergoing trials. By doing so, the authors hope to stimulate further research to help overcome the challenges in treating SUDs.

Efficacy and safety of cytisine versus nortriptyline for smoking cessation: A multicentre, randomized, double-blinded and placebo-controlled trial

BACKGROUND AND OBJECTIVE

Cytisine serves as an affordable smoking cessation aid with acceptable safety profile. However, data comparing its efficacy and safety to standard therapies are limited. We aimed to examine efficacy and safety of cytisine compared to nortriptyline, which is the only approved smoking-cessation medication in Thailand.

METHODS

A 12-month, multicentre, randomized, double-blinded, placebo-controlled trial was conducted. Participants aged ≥20 years who smoked ≥10 cigarettes/day were randomly assigned to receive a 25-day cytisine or a 12-week nortriptyline treatment course. Brief interventions (BI) for smoking cessation were provided to all participants. The primary outcome was biochemically verified continuous abstinence rate (CAR) at 12 months. Additionally, self-reported abstinence, verified by exhaled carbon monoxide (CO) ≤ 10 ppm, was collected at 2 weeks, 1, 3, 6 and 12 months to assess both CAR and 7-day point prevalence abstinence rate (PAR).

RESULTS

A total of 1086 participants were recruited and randomized into cytisine (n = 540) and nortriptyline (n = 546) groups. The 12-month CAR was 12.22% for cytisine and 9.52% for nortriptyline. The relative difference was 0.03 (95% confidence interval [CI]; -0.01 to 0.06) and the relative risk was 1.28 (95% CI; 0.91-1.81). No differences were observed in secondary outcomes between both groups. The incidence of adverse effects from cytisine appeared to be lower than that of nortriptyline.

CONCLUSION

At 12 months, cytisine plus BI was as effective as nortriptyline plus BI for smoking cessation. The adverse events for both cytisine and nortriptyline were minimal and well-tolerated.

Genome-wide meta-analyses of cross substance use disorders in European, African, and Latino ancestry populations

Genetic risks for substance use disorders (SUDs) are due to both SUD-specific and SUD-shared genes. We performed the largest multivariate analyses to date to search for SUD-shared genes using samples of European (EA), African (AA), and Latino (LA) ancestries. By focusing on variants having cross-SUD and cross-ancestry concordant effects, we identified 45 loci. Through gene-based analyses, gene mapping, and gene prioritization, we identified 250 SUD-shared genes. These genes are highly expressed in amygdala, cortex, hippocampus, hypothalamus, and thalamus, primarily in neuronal cells. Cross-SUD concordant variants explained ~ 50% of the heritability of each SUD in EA. The top 5% individuals having the highest polygenic scores were approximately twice as likely to have SUDs as others in EA and LA. Polygenic scores had higher predictability in females than in males in EA. Using real-world data, we identified five drugs targeting identified SUD-shared genes that may be repurposed to treat SUDs.

The cardiovascular safety of tricyclic antidepressants in overdose and in clinical use

Tricyclic antidepressants (TCAs) remain widely prescribed for depression and many other conditions. There may be important differences between individual TCA in regard to their overdose toxicity and their cardiac toxicity in clinical use. We conducted a systematic review to compare the toxicity of individual TCA in overdose and the risk of serious adverse cardiac events occurring with therapeutic doses. We used the fatal toxicity index (FTI) and case fatality ratio as markers of fatality in overdose, and hazard ratios or odds ratios for the risk of cardiovascular adverse events during normal clinical use. In all, 30 reports of mortality in overdose and 14 observational studies assessing the risk of cardiovascular adverse events in clinical use were included. FTI values were of the same order of magnitude (101-102) for all TCAs except lofepramine. Desipramine appears to be somewhat more likely than other TCAs to lead to death in overdose. Amitriptyline, clomipramine, dothiepin/dosulepin, doxepin, trimipramine and imipramine showed broadly similar toxicity and were usually reported to be less toxic than desipramine. Data on nortriptyline were contradictory. Lofepramine had the lowest risk of death in overdose. The rank order of overdose toxicity was broadly consistent between different FTI definitions and between markers used. With respect to the risk of cardiovascular events at clinically relevant exposure, amitriptyline, nortriptyline and lofepramine were associated with a greater risk of in-use cardiotoxicity. All measures of overdose toxicity were subject to external influences and confounding. The continued use of TCAs in depression and other conditions should be minimized when considering their undoubted toxicity in overdose and possible toxicity in normal clinical use.

Antidepressants for smoking cessation

BACKGROUND

The pharmacological profiles and mechanisms of antidepressants are varied. However, there are common reasons why they might help people to stop smoking tobacco: nicotine withdrawal can produce short-term low mood that antidepressants may relieve; and some antidepressants may have a specific effect on neural pathways or receptors that underlie nicotine addiction.

OBJECTIVES

To assess the evidence for the efficacy, harms, and tolerability of medications with antidepressant properties in assisting long-term tobacco smoking cessation in people who smoke cigarettes.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group Specialised Register, most recently on 29 April 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in people who smoked, comparing antidepressant medications with placebo or no pharmacological treatment, an alternative pharmacotherapy, or the same medication used differently. We excluded trials with fewer than six months of follow-up from efficacy analyses. We included trials with any follow-up length for our analyses of harms.

DATA COLLECTION AND ANALYSIS

We extracted data and assessed risk of bias using standard Cochrane methods. Our primary outcome measure was smoking cessation after at least six months' follow-up. We used the most rigorous definition of abstinence available in each trial, and biochemically validated rates if available. Our secondary outcomes were harms and tolerance outcomes, including adverse events (AEs), serious adverse events (SAEs), psychiatric AEs, seizures, overdoses, suicide attempts, death by suicide, all-cause mortality, and trial dropouts due to treatment. We carried out meta-analyses where appropriate.

MAIN RESULTS

We included a total of 124 studies (48,832 participants) in this review, with 10 new studies added to this update version. Most studies recruited adults from the community or from smoking cessation clinics; four studies focused on adolescents (with participants between 12 and 21 years old). We judged 34 studies to be at high risk of bias; however, restricting analyses only to studies at low or unclear risk of bias did not change clinical interpretation of the results.  There was high-certainty evidence that bupropion increased smoking cessation rates when compared to placebo or no pharmacological treatment (RR 1.60, 95% CI 1.49 to 1.72; I2 = 16%; 50 studies, 18,577 participants). There was moderate-certainty evidence that a combination of bupropion and varenicline may have resulted in superior quit rates to varenicline alone (RR 1.21, 95% CI 0.95 to 1.55; I2 = 15%; 3 studies, 1057 participants). However, there was insufficient evidence to establish whether a combination of bupropion and nicotine replacement therapy (NRT) resulted in superior quit rates to NRT alone (RR 1.17, 95% CI 0.95 to 1.44; I2 = 43%; 15 studies, 4117 participants; low-certainty evidence). There was moderate-certainty evidence that participants taking bupropion were more likely to report SAEs than those taking placebo or no pharmacological treatment. However, results were imprecise and the CI also encompassed no difference (RR 1.16, 95% CI 0.90 to 1.48; I2 = 0%; 23 studies, 10,958 participants). Results were also imprecise when comparing SAEs between people randomised to a combination of bupropion and NRT versus NRT alone (RR 1.52, 95% CI 0.26 to 8.89; I2 = 0%; 4 studies, 657 participants) and randomised to bupropion plus varenicline versus varenicline alone (RR 1.23, 95% CI 0.63 to 2.42; I2 = 0%; 5 studies, 1268 participants). In both cases, we judged evidence to be of low certainty. There was high-certainty evidence that bupropion resulted in more trial dropouts due to AEs than placebo or no pharmacological treatment (RR 1.44, 95% CI 1.27 to 1.65; I2 = 2%; 25 studies, 12,346 participants). However, there was insufficient evidence that bupropion combined with NRT versus NRT alone (RR 1.67, 95% CI 0.95 to 2.92; I2 = 0%; 3 studies, 737 participants) or bupropion combined with varenicline versus varenicline alone (RR 0.80, 95% CI 0.45 to 1.45; I2 = 0%; 4 studies, 1230 participants) had an impact on the number of dropouts due to treatment. In both cases, imprecision was substantial (we judged the evidence to be of low certainty for both comparisons). Bupropion resulted in inferior smoking cessation rates to varenicline (RR 0.73, 95% CI 0.67 to 0.80; I2 = 0%; 9 studies, 7564 participants), and to combination NRT (RR 0.74, 95% CI 0.55 to 0.98; I2 = 0%; 2 studies; 720 participants). However, there was no clear evidence of a difference in efficacy between bupropion and single-form NRT (RR 1.03, 95% CI 0.93 to 1.13; I2 = 0%; 10 studies, 7613 participants). We also found evidence that nortriptyline aided smoking cessation when compared with placebo (RR 2.03, 95% CI 1.48 to 2.78; I2 = 16%; 6 studies, 975 participants), and some evidence that bupropion resulted in superior quit rates to nortriptyline (RR 1.30, 95% CI 0.93 to 1.82; I2 = 0%; 3 studies, 417 participants), although this result was subject to imprecision. Findings were sparse and inconsistent as to whether antidepressants, primarily bupropion and nortriptyline, had a particular benefit for people with current or previous depression.

AUTHORS' CONCLUSIONS

There is high-certainty evidence that bupropion can aid long-term smoking cessation. However, bupropion may increase SAEs (moderate-certainty evidence when compared to placebo/no pharmacological treatment). There is high-certainty evidence that people taking bupropion are more likely to discontinue treatment compared with people receiving placebo or no pharmacological treatment. Nortriptyline also appears to have a beneficial effect on smoking quit rates relative to placebo, although bupropion may be more effective. Evidence also suggests that bupropion may be as successful as single-form NRT in helping people to quit smoking, but less effective than combination NRT and varenicline. In most cases, a paucity of data made it difficult to draw conclusions regarding harms and tolerability. Further studies investigating the efficacy of bupropion versus placebo are unlikely to change our interpretation of the effect, providing no clear justification for pursuing bupropion for smoking cessation over other licensed smoking cessation treatments; namely, NRT and varenicline. However, it is important that future studies of antidepressants for smoking cessation measure and report on harms and tolerability.

The Usefulness of In Vitro Percutaneous Absorption Experiments Applying the Infinite Dose Technique to Predict In Vivo Plasma Levels: Comparison of Model-Predicted and Observed Plasma Concentrations of Nortriptyline in Rats

The aims of this study were to evaluate the feasibility of a nortriptyline (NT) formulation for transdermal administration and to assess the usefulness of an estimated kinetic parameter (kout) using the in vitro infinite dose technique to predict in vivo plasma levels when used in combination with pharmacokinetic parameters. To do so, a simple one-compartment model was used to describe the transport of a permeant across a membrane (skin). This model provides relatively simple expressions for the amount of permeant in the skin, the cumulative amount of permeant that crosses the skin, and the flux of permeant, for both the infinite and the finite dose regimens. Transdermal administration of the formulated NT gel to rats resulted in plasma levels of approximately 150 ng/mL between 8 and 30 h post-administration. These levels were higher than the minimum concentration of 40 ng/mL recommended for smoking cessation therapy and slightly higher than the upper limit of the therapeutic range for the treatment of depression in humans. The one-compartment model used to describe transport across the skin was connected to a two-compartment pharmacokinetic model used to predict NT plasma concentrations in rats using the kout determined in vitro and the values of other pharmacokinetic parameters obtained in vivo. The predicted concentrations were close to the observed plasma levels and the time profiles were similar for both types of data. These results show the usefulness of the kout parameter determined in vitro to predict plasma concentrations of drugs administered percutaneously.

Consideration of sex and gender differences in addiction medication response

Substance use continues to contribute to significant morbidity and mortality in the United States, for both women and men, more so than another other preventable health condition. To reduce the public health burden attributable to substances, the National Institute on Drug Abuse and the National Institute on Alcohol Abuse and Alcoholism have identified that medication development for substance use disorder is a high priority research area. Furthermore, both Institutes have stated that research on sex and gender differences in substance use medication development is a critical area. The purpose of the current narrative review is to highlight how sex and gender have been considered (or not) in medication trials for substance use disorders to clarify and summarize what is known regarding sex and gender differences in efficacy and to provide direction to the field to advance medication development that is consistent with current NIH 'sex as a biological variable' (SABV) policy. To that end, we reviewed major classes of abused substances (nicotine, alcohol, cocaine, cannabis, opioids) demonstrating that, sex and gender have not been well-considered in addiction medication development research. However, when adequate data on sex and gender differences have been evaluated (i.e., in tobacco cessation), clinically significant differences in response have been identified between women and men. Across the other drugs of abuse reviewed, data also suggest sex and gender may be predictive of outcome for some agents, although the relatively low representation of women in clinical research samples limits making definitive conclusions. We recommend the incorporation of sex and gender into clinical care guidelines and improved access to publicly available sex-stratified data from medication development investigations.

Interventions for preventing weight gain after smoking cessation

BACKGROUND

Most people who stop smoking gain weight. This can discourage some people from making a quit attempt and risks offsetting some, but not all, of the health advantages of quitting. Interventions to prevent weight gain could improve health outcomes, but there is a concern that they may undermine quitting.

OBJECTIVES

To systematically review the effects of: (1) interventions targeting post-cessation weight gain on weight change and smoking cessation (referred to as 'Part 1') and (2) interventions designed to aid smoking cessation that plausibly affect post-cessation weight gain (referred to as 'Part 2').

SEARCH METHODS

Part 1 - We searched the Cochrane Tobacco Addiction Group's Specialized Register and CENTRAL; latest search 16 October 2020. Part 2 - We searched included studies in the following 'parent' Cochrane reviews: nicotine replacement therapy (NRT), antidepressants, nicotine receptor partial agonists, e-cigarettes, and exercise interventions for smoking cessation published in Issue 10, 2020 of the Cochrane Library. We updated register searches for the review of nicotine receptor partial agonists.

SELECTION CRITERIA

Part 1 - trials of interventions that targeted post-cessation weight gain and had measured weight at any follow-up point or smoking cessation, or both, six or more months after quit day. Part 2 - trials included in the selected parent Cochrane reviews reporting weight change at any time point.

DATA COLLECTION AND ANALYSIS

Screening and data extraction followed standard Cochrane methods. Change in weight was expressed as difference in weight change from baseline to follow-up between trial arms and was reported only in people abstinent from smoking. Abstinence from smoking was expressed as a risk ratio (RR). Where appropriate, we performed meta-analysis using the inverse variance method for weight, and Mantel-Haenszel method for smoking.

MAIN RESULTS

Part 1: We include 37 completed studies; 21 are new to this update. We judged five studies to be at low risk of bias, 17 to be at unclear risk and the remainder at high risk.  An intermittent very low calorie diet (VLCD) comprising full meal replacement provided free of charge and accompanied by intensive dietitian support significantly reduced weight gain at end of treatment compared with education on how to avoid weight gain (mean difference (MD) -3.70 kg, 95% confidence interval (CI) -4.82 to -2.58; 1 study, 121 participants), but there was no evidence of benefit at 12 months (MD -1.30 kg, 95% CI -3.49 to 0.89; 1 study, 62 participants). The VLCD increased the chances of abstinence at 12 months (RR 1.73, 95% CI 1.10 to 2.73; 1 study, 287 participants). However, a second study  found that no-one completed the VLCD intervention or achieved abstinence. Interventions aimed at increasing acceptance of weight gain reported mixed effects at end of treatment, 6 months and 12 months with confidence intervals including both increases and decreases in weight gain compared with no advice or health education. Due to high heterogeneity, we did not combine the data. These interventions increased quit rates at 6 months (RR 1.42, 95% CI 1.03 to 1.96; 4 studies, 619 participants; I2 = 21%), but there was no evidence at 12 months (RR 1.25, 95% CI 0.76 to 2.06; 2 studies, 496 participants; I2 = 26%). Some pharmacological interventions tested for limiting post-cessation weight gain (PCWG) reduced weight gain at the end of treatment (dexfenfluramine, phenylpropanolamine, naltrexone). The effects of ephedrine and caffeine combined, lorcaserin, and chromium were too imprecise to give useful estimates of treatment effects. There was very low-certainty evidence that personalized weight management support reduced weight gain at end of treatment (MD -1.11 kg, 95% CI -1.93 to -0.29; 3 studies, 121 participants; I2 = 0%), but no evidence in the longer-term 12 months (MD -0.44 kg, 95% CI -2.34 to 1.46; 4 studies, 530 participants; I2 = 41%). There was low to very low-certainty evidence that detailed weight management education without personalized assessment, planning and feedback did not reduce weight gain and may have reduced smoking cessation rates (12 months: MD -0.21 kg, 95% CI -2.28 to 1.86; 2 studies, 61 participants; I2 = 0%; RR for smoking cessation 0.66, 95% CI 0.48 to 0.90; 2 studies, 522 participants; I2 = 0%). Part 2: We include 83 completed studies, 27 of which are new to this update. There was low certainty that exercise interventions led to minimal or no weight reduction compared with standard care at end of treatment (MD -0.25 kg, 95% CI -0.78 to 0.29; 4 studies, 404 participants; I2 = 0%). However, weight was reduced at 12 months (MD -2.07 kg, 95% CI -3.78 to -0.36; 3 studies, 182 participants; I2 = 0%). Both bupropion and fluoxetine limited weight gain at end of treatment (bupropion MD -1.01 kg, 95% CI -1.35 to -0.67; 10 studies, 1098 participants; I2 = 3%); (fluoxetine MD -1.01 kg, 95% CI -1.49 to -0.53; 2 studies, 144 participants; I2 = 38%; low- and very low-certainty evidence, respectively). There was no evidence of benefit at 12 months for bupropion, but estimates were imprecise (bupropion MD -0.26 kg, 95% CI -1.31 to 0.78; 7 studies, 471 participants; I2 = 0%). No studies of fluoxetine provided data at 12 months. There was moderate-certainty that NRT reduced weight at end of treatment (MD -0.52 kg, 95% CI -0.99 to -0.05; 21 studies, 2784 participants; I2 = 81%) and moderate-certainty that the effect may be similar at 12 months (MD -0.37 kg, 95% CI -0.86 to 0.11; 17 studies, 1463 participants; I2 = 0%), although the estimates are too imprecise to assess long-term benefit. There was mixed evidence of the effect of varenicline on weight, with high-certainty evidence that weight change was very modestly lower at the end of treatment (MD -0.23 kg, 95% CI -0.53 to 0.06; 14 studies, 2566 participants; I2 = 32%); a low-certainty estimate gave an imprecise estimate of higher weight at 12 months (MD 1.05 kg, 95% CI -0.58 to 2.69; 3 studies, 237 participants; I2 = 0%).

AUTHORS' CONCLUSIONS

Overall, there is no intervention for which there is moderate certainty of a clinically useful effect on long-term weight gain. There is also no moderate- or high-certainty evidence that interventions designed to limit weight gain reduce the chances of people achieving abstinence from smoking.

Synthesis of dibenzocyclohepta[1,2-a]naphthalene derivatives from phenylacetaldehyde and alkynyl benzyl alcohols via sequential electrophilic addition and double Friedel-Crafts reactions

A simple methodology has been developed for the synthesis of substituted 9H-dibenzo[3,4:6,7]-cyclohepta[1,2-a]naphthalenes from phenylacetaldehydes and ortho-alkynyl benzyl alcohols in the presence of a Lewis acid in moderate to good yields within a short reaction time. Interestingly, the reaction proceeds through a highly regioselective electrophilic addition followed by double Friedel-Crafts reaction to form uncommon dibenzo-fused seven-membered carbocycles.

Comparative efficacy and safety of pharmacological interventions for smoking cessation in healthy adults: A network meta-analysis

Smoking is the leading cause of morbidity and mortality in different non-communicable diseases, and cessation leads to immense health benefits. The present network meta-analysis has been conducted to evaluate and compare the effects of available pharmacological interventions for smoking cessation in adults. A standard meta-analysis protocol was developed and after performing a comprehensive literature search on MEDLINE/PubMed, Cochrane databases, and International Clinical Trials Registry Platform, reviewers extracted data from 97 randomized controlled trials. PRISMA guidelines were followed in data extraction, analysis and reporting of findings. Random effects Bayesian network meta-analysis was done to pool the effects across the interventions. Network graph was built, and for closed triangles in the network graph, node splitting analysis was performed. The primary outcome measure was self-reported biochemically verified smoking abstinence at six months. The number of participants achieving continuous abstinence was reported. Data for the number of participants reporting at least one adverse event was also extracted, if available. Combination of nicotine receptor agonist and nicotine replacement therapy had a significant odd of 4.4 (95%CrI:2.2-8.7), bupropion and nicotine receptor agonist 4.0 (95%CrI:2.1-7.7), bupropion and nicotine replacement therapy 3.8 (95%CrI:2.3-6.2), combination nicotine replacement therapy has an odd of 2.6 (95%CrI:1.8-3.8), and nicotine receptor agonist had a significant odd of 2.7 (95%CrI:2.3-3.2) when compared to placebo (moderate quality of evidence) for continuous abstinence at 6 months. When compared with behavioural therapy, the odds ratio of interventions was not statistically significant. Combination of nicotine receptor agonist and nicotine replacement therapy has the highest probability of being the best treatment for abstinence from smoking.

Pharmacological strategies for smoking cessation in patients with chronic obstructive pulmonary disease: a pragmatic review

Introduction: Chronic obstructive pulmonary disease (COPD) is progressive inflammatory disease of the lungs in which smoking plays a significant pathogenic role. Smoking cessation is the only therapeutic intervention which was demonstrated to interfere with disease progression. Smoking cessation intervention can benefit from pharmacological therapies such as nicotine replacement therapies, bupropion, or varenicline which can be given individually or in combination, their effectiveness being demonstrated in various clinical trials enrolling COPD patients.Areas covered: The authors provide a pragmatic discussion of the clinical data of the main studies evaluating therapies for smoking cessation within COPD starting with the seminal Lung Health Study and continuing with more recent ones.Expert opinion: Smoking cessation is one of the most difficult therapeutic interventions in COPD, despite having the highest impact on disease progression and despite the demonstrated benefit of the discussed pharmacological therapies. Potential approaches to maximize its chance of success might be represented by prolonging the time of administration, combinational options, or sequential pharmacotherapy.

Antidepressants for smoking cessation

BACKGROUND

Whilst the pharmacological profiles and mechanisms of antidepressants are varied, there are common reasons why they might help people to stop smoking tobacco. Firstly, nicotine withdrawal may produce depressive symptoms and antidepressants may relieve these. Additionally, some antidepressants may have a specific effect on neural pathways or receptors that underlie nicotine addiction.

OBJECTIVES

To assess the evidence for the efficacy, safety and tolerability of medications with antidepressant properties in assisting long-term tobacco smoking cessation in people who smoke cigarettes.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Specialized Register, which includes reports of trials indexed in the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and PsycINFO, clinicaltrials.gov, the ICTRP, and other reviews and meeting abstracts, in May 2019.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that recruited smokers, and compared antidepressant medications with placebo or no treatment, an alternative pharmacotherapy, or the same medication used in a different way. We excluded trials with less than six months follow-up from efficacy analyses. We included trials with any follow-up length in safety analyses.

DATA COLLECTION AND ANALYSIS

We extracted data and assessed risk of bias using standard Cochrane methods. We also used GRADE to assess the certainty of the evidence. The primary outcome measure was smoking cessation after at least six months follow-up, expressed as a risk ratio (RR) and 95% confidence intervals (CIs). We used the most rigorous definition of abstinence available in each trial, and biochemically validated rates if available. Where appropriate, we performed meta-analysis using a fixed-effect model. Similarly, we presented incidence of safety and tolerance outcomes, including adverse events (AEs), serious adverse events (SAEs), psychiatric AEs, seizures, overdoses, suicide attempts, death by suicide, all-cause mortality, and trial dropout due to drug, as RRs (95% CIs).

MAIN RESULTS

We included 115 studies (33 new to this update) in this review; most recruited adult participants from the community or from smoking cessation clinics. We judged 28 of the studies to be at high risk of bias; however, restricting analyses only to studies at low or unclear risk did not change clinical interpretation of the results. There was high-certainty evidence that bupropion increased long-term smoking cessation rates (RR 1.64, 95% CI 1.52 to 1.77; I2 = 15%; 45 studies, 17,866 participants). There was insufficient evidence to establish whether participants taking bupropion were more likely to report SAEs compared to those taking placebo. Results were imprecise and CIs encompassed no difference (RR 1.16, 95% CI 0.90 to 1.48; I2 = 0%; 21 studies, 10,625 participants; moderate-certainty evidence, downgraded one level due to imprecision). We found high-certainty evidence that use of bupropion resulted in more trial dropouts due to adverse events of the drug than placebo (RR 1.37, 95% CI 1.21 to 1.56; I2 = 19%; 25 studies, 12,340 participants). Participants randomized to bupropion were also more likely to report psychiatric AEs compared with those randomized to placebo (RR 1.25, 95% CI 1.15 to 1.37; I2 = 15%; 6 studies, 4439 participants). We also looked at the safety and efficacy of bupropion when combined with other non-antidepressant smoking cessation therapies. There was insufficient evidence to establish whether combination bupropion and nicotine replacement therapy (NRT) resulted in superior quit rates to NRT alone (RR 1.19, 95% CI 0.94 to 1.51; I2 = 52%; 12 studies, 3487 participants), or whether combination bupropion and varenicline resulted in superior quit rates to varenicline alone (RR 1.21, 95% CI 0.95 to 1.55; I2 = 15%; 3 studies, 1057 participants). We judged the certainty of evidence to be low and moderate, respectively; in both cases due to imprecision, and also due to inconsistency in the former. Safety data were sparse for these comparisons, making it difficult to draw clear conclusions. A meta-analysis of six studies provided evidence that bupropion resulted in inferior smoking cessation rates to varenicline (RR 0.71, 95% CI 0.64 to 0.79; I2 = 0%; 6 studies, 6286 participants), whilst there was no evidence of a difference in efficacy between bupropion and NRT (RR 0.99, 95% CI 0.91 to 1.09; I2 = 18%; 10 studies, 8230 participants). We also found some evidence that nortriptyline aided smoking cessation when compared with placebo (RR 2.03, 95% CI 1.48 to 2.78; I2 = 16%; 6 studies, 975 participants), whilst there was insufficient evidence to determine whether bupropion or nortriptyline were more effective when compared with one another (RR 1.30 (favouring bupropion), 95% CI 0.93 to 1.82; I2 = 0%; 3 studies, 417 participants). There was no evidence that any of the other antidepressants tested (including St John's Wort, selective serotonin reuptake inhibitors (SSRIs), monoamine oxidase inhibitors (MAOIs)) had a beneficial effect on smoking cessation. Findings were sparse and inconsistent as to whether antidepressants, primarily bupropion and nortriptyline, had a particular benefit for people with current or previous depression.

AUTHORS' CONCLUSIONS

There is high-certainty evidence that bupropion can aid long-term smoking cessation. However, bupropion also increases the number of adverse events, including psychiatric AEs, and there is high-certainty evidence that people taking bupropion are more likely to discontinue treatment compared with placebo. However, there is no clear evidence to suggest whether people taking bupropion experience more or fewer SAEs than those taking placebo (moderate certainty). Nortriptyline also appears to have a beneficial effect on smoking quit rates relative to placebo. Evidence suggests that bupropion may be as successful as NRT and nortriptyline in helping people to quit smoking, but that it is less effective than varenicline. There is insufficient evidence to determine whether the other antidepressants tested, such as SSRIs, aid smoking cessation, and when looking at safety and tolerance outcomes, in most cases, paucity of data made it difficult to draw conclusions. Due to the high-certainty evidence, further studies investigating the efficacy of bupropion versus placebo are unlikely to change our interpretation of the effect, providing no clear justification for pursuing bupropion for smoking cessation over front-line smoking cessation aids already available. However, it is important that where studies of antidepressants for smoking cessation are carried out they measure and report safety and tolerability clearly.

Current pharmacologic treatments for smoking cessation and new agents undergoing clinical trials

Smoking causes various diseases and is a major public health threat worldwide. Therefore, promoting smoking cessation is the most important intervention contributing to maintaining the health of smokers and nonsmokers and saving enormous financial expense. We reviewed existing and emerging smoking-cessation pharmacotherapies from the Cochrane Database of Systemic Reviews, PubMed, Ovid, and ClinicalTrials.gov databases. A literature review revealed that bupropion may be appropriate for patients interested in reducing smoking who dislike, or who have failed, nicotine-replacement therapy (NRT). Additionally, varenicline and NRT are efficacious first-line smoking cessation treatments and should be given to all individuals unless contraindicated.

The reviews of this paper are available via the supplementary material section.

Current and Emerging Pharmacotherapies for Cessation of Tobacco Smoking

Tobacco use disorder is a chronic illness. With its high comorbidity rate, it is a major cause of years of life lost or years lived with disability; however, it is also considered the most preventable cause of death in developed countries. Since the development of nicotine replacement therapy (NRT) in 1978, treatment options have continued to evolve and expand. Despite this, currently available treatments remain insufficient, with less than 25% of smokers remaining abstinent 1 year after treatment. In this article, we review existing and emerging smoking cessation pharmacotherapies, with a special emphasis on the most promising agents that are currently being investigated. A search of the Cochrane Database of Systematic Reviews and the PubMed, Ovid, and ClinicalTrials.gov databases (August 2 to September 1, 2017) was undertaken for articles on smoking cessation pharmacotherapies, applying no language restrictions. More than 40 pharmacotherapies were reviewed including conventional pharmacotherapies-NRT, bupropion, and varenicline (all approved by the U.S. Food and Drug Administration as first-line treatment of smoking cessation)-and novel therapies: cytisine, N-acetylcysteine, cycloserine, memantine, baclofen, topiramate, galantamine, and bromocriptine. Studies of combination NRT and varenicline showed the greatest smoking cessation rates. Clonidine and nortriptyline are second-line treatments used when first-line treatments fail or are contraindicated, or by patient preference. Some novel therapies, especially acetylcholinesterase inhibitors, cytisine, and N-acetylcysteine, display promising results. Because the results of randomized clinical trials were reported using varied end points and outcome measures, direct comparisons between different pharmacotherapies cannot easily be evaluated. Additional high-quality randomized double-blind placebo-controlled trials with long-term follow-up, using validated sustained abstinence measures, are needed to find more effective smoking cessation aids.

Why are Antidepressant Drugs Effective Smoking Cessation Aids?

BACKGROUND

Before the advent of varenicline, antidepressant drugs were reported to exhibit better clinical efficacy than nicotine replacement therapy as smoking cessation aids. The most studied is bupropion, a clinically-effective antidepressant, the first to be marketed throughout Europe for smoking cessation. Since depression and tobacco smoking have a high incidence of cooccurrence, this would implicate an underlying link between these two conditions. If this correlation can be confirmed, then by treating one condition the related state would also be treated.

OBJECTIVES

This review article will evaluate the various theories relating to the use of antidepressant drugs as smoking cessation aids and the underlying mechanisms link tobacco smoking and depression to explain the action of antidepressants in smoking cessation. One plausible theory of self-medication which proposes that people take nicotine to treat their own depressive symptoms and the affective withdrawal symptoms seen with abstinence from the drug. If the depression can instead be treated with antidepressants, then they may stop smoking altogether. Another theory is that the neurobiological pathways underlying smoking and depression may be similar. By targeting the pathways of depression in the brain, antidepressants would also treat the pathways affected by smoking and ease nicotine cravings and withdrawal. The role of genetic variation predisposing an individual to depression and initiation of tobacco smoking has also been discussed as a potential link between the two conditions. Such variation could either occur within the neurobiological pathways involved in both disorders or it could lead to an individual being depressed and selfmedicating with nicotine.

Psychological, pharmacological, and combined smoking cessation interventions for smokers with current depression: A systematic review and meta-analysis

We conducted a systematic literature review and meta-analysis (ID: CRD42016051017) of smoking cessation interventions for patients with current depression. We examined the effectiveness of smoking cessation treatments in improving abstinence rates and depressive symptoms. The following electronic databases were used for potentially eligible studies: PUBMED, PSYCINFO, DIALNET and WEB OF KNOWLEDGE. The search terms used were: smoking cessation, depressive disorder, depression, mood, depressive, depressed, smoking, smokers, nicotine, nicotine dependence, and tobacco cigarette smoking. The methodological quality of included studies was assessed using the Effective Public Health Practice Project Quality assessment tool (EPHPP). Of the 6,584 studies identified, 20 were eligible and included in the review. Trial designs of studies were 16 randomized controlled trials and 4 secondary studies. Studies included three types of intervention: psychological (6/30%), pharmacological (6/30%) or combined (8/40%). Four trials comprised special populations of smokers. Four studies received a strong methodological quality, 7 were scored as moderate and 9 studies received a weak methodological rating. Analyses of effectiveness showed that smoking cessation interventions appear to increase short-term and long-term smoking abstinence in individuals with current depression. Subgroup analyses revealed stronger effects among studies that provided pharmacological treatments than in studies using psychological treatments. However, the evidence is weak due to the small number of studies. Smoking abstinence appears to be associated with an improvement in depressive symptoms. Heterogeneity in protocols in similar types of treatment also prevent firm conclusions being drawn on the effectiveness of any particular treatment model to optimally manage abstinence among depressed smokers. Further research is required to strengthen the evidence base.

Construction of dibenzo-fused seven- to nine-membered carbocycles via Brønsted acid-promoted intramolecular Friedel-Crafts-type alkenylation

Brønsted acid-promoted intramolecular hydroarylation of alkynylbenzenes carrying an arylalkyl group at the ortho-position leads to alkylidenedibenzo[a,d]cycloheptenes, -octenes and -nonenes in up to quantitative yield with complete regioselectivity. The scope and limitation of this reaction and application to the synthesis of tricyclic antidepressants are described.

Negative affective states and cognitive impairments in nicotine dependence

Smokers have substantial individual differences in quit success in response to current treatments for nicotine dependence. This observation may suggest that different underlying motivations for continued tobacco use across individuals and nicotine cessation may require different treatments in different individuals. Although most animal models of nicotine dependence emphasize the positive reinforcing effects of nicotine as the major motivational force behind nicotine use, smokers generally report that other consequences of nicotine use, including the ability of nicotine to alleviate negative affective states or cognitive impairments, as reasons for continued smoking. These states could result from nicotine withdrawal, but also may be associated with premorbid differences in affective and/or cognitive function. Effects of nicotine on cognition and affect may alleviate these impairments regardless of their premorbid or postmorbid origin (e.g., before or after the development of nicotine dependence). The ability of nicotine to alleviate these symptoms would thus negatively reinforce behavior, and thus maintain subsequent nicotine use, contributing to the initiation of smoking, the progression to dependence and relapse during quit attempts. The human and animal studies reviewed here support the idea that self-medication for pre-morbid and withdrawal-induced impairments may be more important factors in nicotine addiction and relapse than has been previously appreciated in preclinical research into nicotine dependence. Given the diverse beneficial effects of nicotine under these conditions, individuals might smoke for quite different reasons. This review suggests that inter-individual differences in the diverse effects of nicotine associated with self-medication and negative reinforcement are an important consideration in studies attempting to understand the causes of nicotine addiction, as well as in the development of effective, individualized nicotine cessation treatments.

Neurobiological Bases of Cue- and Nicotine-induced Reinstatement of Nicotine Seeking: Implications for the Development of Smoking Cessation Medications

A better understanding of the neurobiological factors that contribute to relapse to smoking is needed for the development of efficacious smoking cessation medications. Reinstatement procedures allow the preclinical assessment of several factors that contribute to relapse in humans, including re-exposure to nicotine via tobacco smoking and the presentation of stimuli that were previously associated with nicotine administration (i.e., conditioned stimuli). This review provides an integrated discussion of the results of animal studies that used reinstatement procedures to assess the efficacy of pharmacologically targeting various neurotransmitter systems in attenuating the cue- and nicotine-induced reinstatement of nicotine seeking. The results of these animal studies have increased our understanding of the neurobiological processes that mediate the conditioned effects of stimuli that trigger reinstatement to nicotine seeking. Thus, these findings provide important insights into the neurobiological substrates that modulate relapse to tobacco smoking in humans and the ongoing search for novel efficacious smoking cessation medications.

Antidepressants for smoking cessation

BACKGROUND

There are at least three reasons to believe antidepressants might help in smoking cessation. Firstly, nicotine withdrawal may produce depressive symptoms or precipitate a major depressive episode and antidepressants may relieve these. Secondly, nicotine may have antidepressant effects that maintain smoking, and antidepressants may substitute for this effect. Finally, some antidepressants may have a specific effect on neural pathways (e.g. inhibiting monoamine oxidase) or receptors (e.g. blockade of nicotinic-cholinergic receptors) underlying nicotine addiction.

OBJECTIVES

The aim of this review is to assess the effect and safety of antidepressant medications to aid long-term smoking cessation. The medications include bupropion; doxepin; fluoxetine; imipramine; lazabemide; moclobemide; nortriptyline; paroxetine; S-Adenosyl-L-Methionine (SAMe); selegiline; sertraline; St. John's wort; tryptophan; venlafaxine; and zimeledine.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group Specialised Register which includes reports of trials indexed in the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and PsycINFO, and other reviews and meeting abstracts, in July 2013.

SELECTION CRITERIA

We considered randomized trials comparing antidepressant medications to placebo or an alternative pharmacotherapy for smoking cessation. We also included trials comparing different doses, using pharmacotherapy to prevent relapse or re-initiate smoking cessation or to help smokers reduce cigarette consumption. We excluded trials with less than six months follow-up.

DATA COLLECTION AND ANALYSIS

We extracted data and assessed risk of bias using standard methodological procedures expected by the Cochrane Collaboration.The main outcome measure was abstinence from smoking after at least six months follow-up in patients smoking at baseline, expressed as a risk ratio (RR). We used the most rigorous definition of abstinence available in each trial, and biochemically validated rates if available. Where appropriate, we performed meta-analysis using a fixed-effect model.

MAIN RESULTS

Twenty-four new trials were identified since the 2009 update, bringing the total number of included trials to 90. There were 65 trials of bupropion and ten trials of nortriptyline, with the majority at low or unclear risk of bias. There was high quality evidence that, when used as the sole pharmacotherapy, bupropion significantly increased long-term cessation (44 trials, N = 13,728, risk ratio [RR] 1.62, 95% confidence interval [CI] 1.49 to 1.76). There was moderate quality evidence, limited by a relatively small number of trials and participants, that nortriptyline also significantly increased long-term cessation when used as the sole pharmacotherapy (six trials, N = 975, RR 2.03, 95% CI 1.48 to 2.78). There is insufficient evidence that adding bupropion (12 trials, N = 3487, RR 1.9, 95% CI 0.94 to 1.51) or nortriptyline (4 trials, N = 1644, RR 1.21, 95% CI 0.94 to 1.55) to nicotine replacement therapy (NRT) provides an additional long-term benefit. Based on a limited amount of data from direct comparisons, bupropion and nortriptyline appear to be equally effective and of similar efficacy to NRT (bupropion versus nortriptyline 3 trials, N = 417, RR 1.30, 95% CI 0.93 to 1.82; bupropion versus NRT 8 trials, N = 4096, RR 0.96, 95% CI 0.85 to 1.09; no direct comparisons between nortriptyline and NRT). Pooled results from four trials comparing bupropion to varenicline showed significantly lower quitting with bupropion than with varenicline (N = 1810, RR 0.68, 95% CI 0.56 to 0.83). Meta-analyses did not detect a significant increase in the rate of serious adverse events amongst participants taking bupropion, though the confidence interval only narrowly missed statistical significance (33 trials, N = 9631, RR 1.30, 95% CI 1.00 to 1.69). There is a risk of about 1 in 1000 of seizures associated with bupropion use. Bupropion has been associated with suicide risk, but whether this is causal is unclear. Nortriptyline has the potential for serious side-effects, but none have been seen in the few small trials for smoking cessation.There was no evidence of a significant effect for selective serotonin reuptake inhibitors on their own (RR 0.93, 95% CI 0.71 to 1.22, N = 1594; 2 trials fluoxetine, 1 paroxetine, 1 sertraline) or as an adjunct to NRT (3 trials of fluoxetine, N = 466, RR 0.70, 95% CI 0.64 to 1.82). Significant effects were also not detected for monoamine oxidase inhibitors (RR 1.29, 95% CI 0.93 to 1.79, N = 827; 1 trial moclobemide, 5 selegiline), the atypical antidepressant venlafaxine (1 trial, N = 147, RR 1.22, 95% CI 0.64 to 2.32), the herbal therapy St John's wort (hypericum) (2 trials, N = 261, RR 0.81, 95% CI 0.26 to 2.53), or the dietary supplement SAMe (1 trial, N = 120, RR 0.70, 95% CI 0.24 to 2.07).

AUTHORS' CONCLUSIONS

The antidepressants bupropion and nortriptyline aid long-term smoking cessation. Adverse events with either medication appear to rarely be serious or lead to stopping medication. Evidence suggests that the mode of action of bupropion and nortriptyline is independent of their antidepressant effect and that they are of similar efficacy to nicotine replacement. Evidence also suggests that bupropion is less effective than varenicline, but further research is needed to confirm this finding. Evidence suggests that neither selective serotonin reuptake inhibitors (e.g. fluoxetine) nor monoamine oxidase inhibitors aid cessation.

Pharmacotherapy of smoking cessation

Nicotine in tobacco smoke causes not only pathophysiological changes in the smoker's body, but also develops tolerance to its own action with repeated use. Repeated exposure to nicotine develops neuroadaptation of the receptors, resulting in tolerance to many of the effects of nicotine. Pharmacotherapies for smoking cessation should reduce withdrawal symptoms and block the reinforcing effects of nicotine without causing excessive adverse effects. All forms of nicotine replacement therapy (NRT) - gum, patches and inhaler - and bupropion are safe and effective for increasing smoking cessation rates in the short and long-term use. Combination NRT (more than one therapy) may be indicated in patients who have failed monotherapy.

Two decades of smoking cessation treatment research on smokers with depression: 1990-2010

INTRODUCTION

Adults with depression smoke at higher rates than other adults leaving a large segment of this population, who already incur increased health-related risks, vulnerable to the enormous harmful consequences of smoking. Yet, the impact that depression has on smoking cessation is not clear due to the mixed results of past research. The primary aims of this review were to synthesize the research examining the relationship of depression to smoking cessation outcomes over a 20-year period, to examine the gender and racial composition of these studies, and to identify directions for future research.

METHODS

Potential articles published between January 1, 1990 and December 31, 2010 were identified through a MEDLINE search of the terms "clinical trial," "depression," and "smoking cessation." 68 studies used all three terms and met the inclusion criteria.

RESULTS

The majority of studies examined either a past diagnosis of major depression or current depression symptoms. Within the few studies that examined the interaction of gender and depression on smoking cessation, depression had a greater impact on treatment outcomes for women than men. No study reported examining the interactive impact of race and depression on treatment outcomes.

CONCLUSIONS

Although attention to the relationship of depression and smoking cessation outcomes has increased over the past 20 years, little information exists to inform a treatment approach for smokers with Current Major Depressive Disorder, Dysthymia, and Minor Depression and few studies report gender and racial differences in the relationship of depression and smoking cessation outcomes, thus suggesting major areas for targeted research.

Tobacco addiction and the dysregulation of brain stress systems

Tobacco is a highly addictive drug and is one of the most widely abused drugs in the world. The first part of this review explores the role of stressors and stress-associated psychiatric disorders in the initiation of smoking, the maintenance of smoking, and relapse after a period of abstinence. The reviewed studies indicate that stressors facilitate the initiation of smoking, decrease the motivation to quit, and increase the risk for relapse. Furthermore, people with depression or an anxiety disorder are more likely to smoke than people without these disorders. The second part of this review describes animal studies that investigated the role of brain stress systems in nicotine addiction. These studies indicate that corticotropin-releasing factor, Neuropeptide Y, the hypocretins, and norepinephrine play a pivotal role in nicotine addiction. In conclusion, the reviewed studies indicate that smoking briefly decreases subjective stress levels but also leads to a further dysregulation of brain stress systems. Drugs that decrease the activity of brain stress systems may diminish nicotine withdrawal and improve smoking cessation rates.

Translating the smoking cessation properties of the antidepressant nortriptyline using reinforcing, discriminative and aversive stimulus effects of nicotine in rats

RATIONALE

The antidepressant nortriptyline is a second-line pharmacotherapy for smoking cessation. Given that there is limited preclinical data available on the effects of nortriptyline on responses to nicotine, the present study sought to evaluate its effects on the reinforcing, discriminative stimulus (DS) and aversive effects of nicotine in male hooded Lister rats.

METHODS

The effects of nortriptyline (0, 1, 3 and 10 mg/kg, i.p.) on responding under the control of a second order schedule of nicotine (0.03 mg/kg per infusion) intravenous self-administration (IVSA; n = 7), food-maintained responding (n = 6), discrimination of nicotine (0.2 mg/kg, s.c.) from saline in a two-lever procedure controlled by a fixed ratio and variable interval schedule of food reinforcement (n = 12) and on the development of nicotine- and lithium-induced conditioned taste aversions (CTA) (n = 8 per dose of nortriptyline) were examined.

RESULTS

Nortriptyline (3 mg/kg) reduced responding for nicotine in the drug-free interval in which behaviour was supported by nicotine-associated cues and subsequent intervals in which nicotine was available; however, food-maintained responding was also reduced at the same dose. Nortriptyline (3 mg/kg) blocked the development of a nicotine-induced CTA but not a lithium-induced CTA, indicating that these effects are unlikely to be due to non-specific effects of nortriptyline on taste perception or learning. Lastly, nortriptyline had no effect on the DS properties of nicotine.

CONCLUSIONS

Nortriptyline appears to attenuate the reinforcing and aversive stimulus properties of nicotine, which may mediate its anti-smoking effects. However, the results should be interpreted with caution, as non-specific effects of nortriptyline may have contributed to these findings.

Interventions for preventing weight gain after smoking cessation

BACKGROUND

Most people who stop smoking gain weight. There are some interventions that have been designed to reduce weight gain when stopping smoking. Some smoking cessation interventions may also limit weight gain although their effect on weight has not been reviewed.

OBJECTIVES

To systematically review the effect of: (1) Interventions targeting post-cessation weight gain on weight change and smoking cessation.(2) Interventions designed to aid smoking cessation that may also plausibly affect weight on post-cessation weight change.

SEARCH METHODS

Part 1 - We searched the Cochrane Tobacco Addiction Group's Specialized Register and CENTRAL in September 2011.Part 2 - In addition we searched the included studies in the following "parent" Cochrane reviews: nicotine replacement therapy (NRT), antidepressants, nicotine receptor partial agonists, cannabinoid type 1 receptor antagonists and exercise interventions for smoking cessation published in Issue 9, 2011 of the Cochrane Library.

SELECTION CRITERIA

Part 1 - We included trials of interventions that were targeted at post-cessation weight gain and had measured weight at any follow up point and/or smoking cessation six or more months after quit day.Part 2 - We included trials that had been included in the selected parent Cochrane reviews if they had reported weight gain at any time point.

DATA COLLECTION AND ANALYSIS

We extracted data on baseline characteristics of the study population, intervention, outcome and study quality. Change in weight was expressed as difference in weight change from baseline to follow up between trial arms and was reported in abstinent smokers only. Abstinence from smoking was expressed as a risk ratio (RR). We used the most rigorous definition of abstinence available in each trial. Where appropriate, we performed meta-analysis using the inverse variance method for weight and Mantel-Haenszel method for smoking using a fixed-effect model.

MAIN RESULTS

Part 1: Some pharmacological interventions tested for limiting post cessation weight gain (PCWG) resulted in a significant reduction in WG at the end of treatment (dexfenfluramine (Mean difference (MD) -2.50 kg, 95% confidence interval (CI) -2.98 to -2.02, 1 study), phenylpropanolamine (MD -0.50 kg, 95% CI -0.80 to -0.20, N=3), naltrexone (MD -0.78 kg, 95% CI -1.52 to -0.05, N=2). There was no evidence that treatment reduced weight at 6 or 12 months (m). No pharmacological intervention significantly affected smoking cessation rates.Weight management education only was associated with no reduction in PCWG at end of treatment (6 or 12m). However these interventions significantly reduced abstinence at 12m (Risk ratio (RR) 0.66, 95% CI 0.48 to 0.90, N=2). Personalised weight management support reduced PCWG at 12m (MD -2.58 kg, 95% CI -5.11 to -0.05, N=2) and was not associated with a significant reduction of abstinence at 12m (RR 0.74, 95% CI 0.39 to 1.43, N=2). A very low calorie diet (VLCD) significantly reduced PCWG at end of treatment (MD -3.70 kg, 95% CI -4.82 to -2.58, N=1), but not significantly so at 12m (MD -1.30 kg, 95% CI -3.49 to 0.89, N=1). The VLCD increased chances of abstinence at 12m (RR 1.73, 95% CI 1.10 to 2.73, N=1). There was no evidence that cognitive behavioural therapy to allay concern about weight gain (CBT) reduced PCWG, but there was some evidence of increased PCWG at 6m (MD 0.74, 95% CI 0.24 to 1.24). It was associated with improved abstinence at 6m (RR 1.83, 95% CI 1.07 to 3.13, N=2) but not at 12m (RR 1.25, 95% CI 0.83 to 1.86, N=2). However, there was significant statistical heterogeneity.Part 2: We found no evidence that exercise interventions significantly reduced PCWG at end of treatment (MD -0.25 kg, 95% CI -0.78 to 0.29, N=4) however a significant reduction was found at 12m (MD -2.07 kg, 95% CI -3.78 to -0.36, N=3).Both bupropion and fluoxetine limited PCWG at the end of treatment (bupropion MD -1.12 kg, 95% CI -1.47 to -0.77, N=7) (fluoxetine MD -0.99 kg, 95% CI -1.36 to -0.61, N=2). There was no evidence that the effect persisted at 6m (bupropion MD -0.58 kg, 95% CI -2.16 to 1.00, N=4), (fluoxetine MD -0.01 kg, 95% CI -1.11 to 1.10, N=2) or 12m (bupropion MD -0.38 kg, 95% CI -2.00 to 1.24, N=4). There were no data on WG at 12m for fluoxetine.Overall, treatment with NRT attenuated PCWG at the end of treatment (MD -0.69 kg, 95% CI -0.88 to -0.51, N=19), with no strong evidence that the effect differed for the different forms of NRT. There was evidence of significant statistical heterogeneity caused by one study which reported a 4.3 kg reduction in PCWG due to NRT. With this study removed, the difference in weight change at end of treatment was -0.45 kg (95% CI -0.66 to -0.27, N=18). There was no evidence of an effect on PCWG at 12m (MD -0.42 kg, 95% CI -0.92 to 0.08, N=15).We found evidence that varenicline significantly reduced PCWG at end of treatment (MD -0.41 kg, 95% CI -0.63 to -0.19, N=11), but this effect was not maintained at 6 or 12m. Three studies compared the effect of bupropion to varenicline. Participants taking bupropion gained significantly less weight at the end of treatment (-0.51 kg (95% CI -0.93 to -0.09 kg), N=3). Direct comparison showed no significant difference in PCWG between varenicline and NRT.

AUTHORS' CONCLUSIONS

Although some pharmacotherapies tested to limit PCWG show evidence of short-term success, other problems with them and the lack of data on long-term efficacy limits their use. Weight management education only, is not effective and may reduce abstinence. Personalised weight management support may be effective and not reduce abstinence, but there are too few data to be sure. One study showed a VLCD increased abstinence but did not prevent WG in the longer term. CBT to accept WG did not limit PCWG and may not promote abstinence in the long term. Exercise interventions significantly reduced weight in the long term, but not the short term. More studies are needed to clarify whether this is an effect of treatment or a chance finding. Bupropion, fluoxetine, NRT and varenicline reduce PCWG while using the medication. Although this effect was not maintained one year after stopping smoking, the evidence is insufficient to exclude a modest long-term effect. The data are not sufficient to make strong clinical recommendations for effective programmes to prevent weight gain after cessation.

Safety of nortriptyline at equivalent therapeutic doses for smoking cessation: a systematic review and meta-analysis

BACKGROUND

The limited use of nortriptyline for smoking cessation is likely due to concerns about its serious adverse effects.

OBJECTIVE

To examine the safety of nortriptyline at doses equivalent to those used in aiding smoking cessation.

DATA SOURCES

A systematic search of relevant articles in MEDLINE, EMBASE, the Cochrane Database of Systematic Reviews, CINAHL, PsychINFO, WHO publications and the Clinical Trials database (through November 2008).

STUDY SELECTION

All studies of nortriptyline at doses between 75 and 100 mg in any indication were reviewed.

DATA EXTRACTION

The quality of included studies was assessed based on the Jadad score. Data were extracted using a data extraction form.

DATA SYNTHESIS

From 442 potentially relevant articles identified, 17 studies met our selection criteria and were included for data analysis. Indications for nortriptyline in these studies were smoking cessation (eight studies), depression (five studies), neuropathic pain (three studies) and schizophrenia (one study). 2885 individuals participated in these studies, with exposure time ranging between 4 and 12 weeks. The major comparator used in these trials was placebo. Overall, no life-threatening events occurred in these studies. Orthostatic hypotension was significantly higher in nortriptyline users than in comparator groups (relative risk 2.8; 95% CI 1.4, 5.3). Other adverse events significantly associated with nortriptyline were anticholinergic-related effects including drowsiness, dizziness, gastrointestinal disturbance and dysgeusia.

CONCLUSIONS

Current evidence suggests that nortriptyline, at doses between 75 and 100 mg, is not significantly associated with serious adverse events when administered in patients without underlying cardiovascular disease.

Targeting nicotine addiction: the possibility of a therapeutic vaccine

Cigarette smoking is the primary cause of lung cancer, cardiovascular diseases, reproductive disorders, and delayed wound healing all over the world. The goals of smoking cessation are both to reduce health risks and to improve quality of life. The development of novel and more effective medications for smoking cessation is crucial in the treatment of nicotine dependence. Currently, first-line smoking cessation therapies include nicotine replacement products and bupropion. The partial nicotinic receptor agonist, varenicline, has recently been approved by the US Food and Drug Administration (FDA) for smoking cessation. Clonidine and nortriptyline have demonstrated some efficacy, but side effects may limit their use to second-line treatment products. Other therapeutic drugs that are under development include rimonabant, mecamylamine, monoamine oxidase inhibitors, and dopamine D3 receptor antagonists. Nicotine vaccines are among newer products seeking approval from the FDA. Antidrug vaccines are irreversible, provide protection over years and need booster injections far beyond the critical phase of acute withdrawal symptoms. Interacting with the drug in the blood rather than with a receptor in the brain, the vaccines are free of side effects due to central interaction. For drugs like nicotine, which interacts with different types of receptors in many organs, this is a further advantage. Three anti-nicotine vaccines are today in an advanced stage of clinical evaluation. Results show that the efficiency of the vaccines is directly related to the antibody levels, a fact which will help to optimize the vaccine effect. The vaccines are expected to appear on the market between 2011 and 2012.

A real-life study of the effectiveness of different pharmacological approaches to the treatment of smoking cessation: re-discussing the predictors of success

OBJECTIVE

To evaluate the effectiveness of nicotine replacement therapy (NRT), bupropion, nortriptyline and combination therapy and describe factors associated with treatment success.

INTRODUCTION

Clinical trials clearly demonstrate the efficacy of pharmacotherapy in smoking cessation. However, it is only after its use in real-life settings that clinical effectiveness and limitations of a treatment are fully known.

METHODS

Patients attended a four-session cognitive-behavioral program and received medicines free of charge. Abstinence from smoking was assessed at each visit.

RESULTS

A total of 868 smokers (68.8% women) were included. Their mean age was 49.6 years; the amount smoked was 25 cigarettes/day and the Fagerströ m Score was 6.6. Abstinence rates after 6 months and 1 year were 36.5% and 33.6%. In univariate analysis, male gender, age (>50), higher number of cigarettes smoked, cardiovascular comorbidities, longer interval from the last cigarette and combined treatment of nortriptyline plus NRT were predictive of abstinence, while neuropsychiatric comorbidities and the answer ''yes'' to the question ''Do you smoke more often during the first hours after waking'' were correlated with failure. In a multivariate model, predictors of abstinence were neuropsychiatric comorbidities, the answer ''yes'' to the question ''Do you smoke more often during the first hours after waking'' and combined treatment of nortriptyline plus NRT. Male gender and a longer period from the last cigarette were correlated with lower abstinence rate.

CONCLUSION

Satisfactory success rates were obtained in a teaching hospital. Factors such as age, daily cigarette consumption, number of pack-years and dependency score were not reliable markers of abstinence. The combination nortriptyline+NRT was independently associated with higher abstinence rates.

Effects of prazosin, clonidine, and propranolol on the elevations in brain reward thresholds and somatic signs associated with nicotine withdrawal in rats

RATIONALE

Tobacco withdrawal is characterized by a negative mood state and relatively mild somatic symptoms. Increased noradrenergic transmission has been reported to play an important role in opioid withdrawal, but little is known about the role of noradrenergic transmission in nicotine withdrawal.

OBJECTIVES

The aim of these experiments was to investigate the effects of prazosin, clonidine, and propranolol on the negative mood state and somatic signs associated with nicotine withdrawal in rats.

METHODS

A discrete-trial intracranial self-stimulation procedure was used to assess the negative affective state of nicotine withdrawal. Elevations in brain reward thresholds are indicative of a deficit in brain reward function.

RESULTS

In all the experiments, the nicotinic acetylcholine receptor antagonist mecamylamine (3 mg/kg) elevated the brain reward thresholds of the nicotine-treated rats and did not affect those of the control rats. The α1-adrenergic receptor antagonist prazosin (0.0625 and 0.125 mg/kg) dose-dependently attenuated the elevations in brain reward thresholds associated with precipitated nicotine withdrawal. The α2-adrenergic receptor agonist clonidine (10-40 μg/kg) and the nonselective β-adrenergic receptor antagonist propranolol (2.5-10 mg/kg) did not attenuate the elevations in brain reward thresholds associated with nicotine withdrawal. Furthermore, mecamylamine (2 mg/kg) induced more somatic signs in the nicotine-treated rats than in the control rats. Clonidine and propranolol, but not prazosin, decreased the total number of somatic signs associated with nicotine withdrawal.

CONCLUSION

Blockade of α1-adrenergic receptors attenuates the deficit in brain reward function associated with nicotine withdrawal. Antagonism of β-adrenergic receptors or stimulation of α2-adrenergic receptors attenuates the somatic symptoms of nicotine withdrawal.

Comparison of available treatments for tobacco addiction

Cigarette smoking is a major public health problem that causes more than 5 million deaths annually worldwide. Cigarette smoking is especially common among individuals with psychiatric comorbidity, including individuals with primary psychiatric disorders and other addictions. Effective behavioral and pharmacologic treatments for smoking cessation are available. Behavioral treatments including brief (< 3 min) counseling by physicians are effective. Seven first-line pharmacologic treatments are currently available: five nicotine replacement therapies, bupropion, and varenicline. In addition, clonidine and nortriptyline are second-line treatments for smoking cessation. These treatments increase the chances of quitting smoking by two- to threefold, supporting their use in smokers who are motivated to quit. However, effective treatments for many subpopulations, including smokers with psychiatric comorbidities as well as adolescent, pregnant, or postpartum smokers, remain to be developed and represent an important challenge.

The alpha2 adrenergic receptor antagonist idazoxan, but not the serotonin-2A receptor antagonist M100907, partially attenuated reward deficits associated with nicotine, but not amphetamine, withdrawal in rats

Based on phenomenological similarities between anhedonia (reward deficits) associated with drug withdrawal and the negative symptoms of schizophrenia, we showed previously that the atypical antipsychotic clozapine attenuated reward deficits associated with psychostimulant withdrawal. Antagonism of alpha(2) adrenergic and 5-HT(2A) receptors may contribute to these effects of clozapine. We investigated here whether blockade of alpha(2) or 5-HT(2A) receptors by idazoxan and M100907, respectively, would reverse anhedonic aspects of psychostimulant withdrawal. Idazoxan treatment facilitated recovery from spontaneous nicotine, but not amphetamine, withdrawal by attenuating reward deficits and increase the number of somatic signs. Thus, alpha(2) adrenoceptor blockade may have beneficial effects against nicotine withdrawal and may be involved in the effects of clozapine previously observed. M100907 worsened the anhedonia associated with nicotine and amphetamine withdrawal, suggesting that monotherapy with M100907 may exacerbate the expression of the negative symptoms of schizophrenia or nicotine withdrawal symptoms in people, including schizophrenia patients, attempting to quit smoking.

A longitudinal study on the causal association between smoking and depression

OBJECTIVES

The objective of this study was to analyze the causal relationship between smoking and depression using longitudinal data.

METHODS

Two waves of the Korea Welfare Panel collected in 2006 and 2007 were used. The sample consisted of 14 426 in 2006 and 13 052 in 2007 who were aged 20 and older. Smoking was measured by smoking amount (none/<half pack a day / < one pack a day / < two packs a day / >or= two packs). Depression was defined when the summated CESD (center for epidemiological studies depression)-11 score was greater than or equal to 16. The causal relationship between smoking and depression was tested using logistic regression. In order to test the causal effect of smoking on depression, depression at year 2 was regressed on smoking status at year 1 only using the sample without depression at year 1. Likewise, smoking status at year 2 was regressed on depression at year 1 only using those who were not smoking at year 1 in order to test the causal effect of depression on smoking. The statistical package used was Stata 10.0. Sampling weights were applied to obtain the population estimation.

RESULTS

The logistic regression testing for the causal relationship between smoking and depression showed that smoking at year 1 was significantly related to depression at year 2. Smoking amounts associated with depression were different among age groups. On the other hand, the results from the logistic regression testing for the opposite direction of the relationship between smoking and depression found no significant association regardless of age group.

CONCLUSIONS

The study results showed some evidence that smoking caused depression but not the other way around.

Wistar rat skin as surrogate for human skin in nortriptyline hydrochloride patch studies

Six different matrices were prepared containing nortriptyline hydrochloride (NTH) with hydroxypropyl-methyl-cellulose as polymer. A mixture of transdermal enhancers was included as part of the vehicle. Diffusion studies were carried out through Wistar rat full thickness skin using Franz cells. They were compared with previously determined human heat separated epidermis in order to test if this animal can be used as model for in vivo assays. A linear correlation was obtained between NTH diffusion coefficients through both skin types (r2=0.996).

Nortriptyline for smoking cessation: release and human skin diffusion from patches

The objective of this work was to develop a simple and inexpensive transdermal formulation containing Nortriptyline Hydrochloride (NTH) for smoking cessation support therapy. Hydroxypropyl-methyl-cellulose was chosen as polymer and a mixture of transdermal enhancers (selected from previous research) was incorporated. The formulations were characterised in terms of appearance, thickness, uniformity of NTH content, release and skin permeation. Release studies demonstrated controlled release for four formulations. Diffusion studies were performed through human heat separated epidermis (HHSE) using Franz Diffusion Cells (FDC). Patches provided different fluxes varying from 20.39+/-7.09 microg/(cm(2) h) to 256.19+/-94.62 microg/(cm(2) h). The penetration profiles of NTH within the stratum corneum (SC) and deeper skin layers (DSL) were established after three administration periods (3 h, 6 h, and 24 h). Skin changes induced by the application of the patches were observed by confocal laser scanning microscopy (CLSM). The highest flux obtained would provide the recommended doses for smoke cessation support therapy (25-75 mg per day) with a 2 cm x 2 cm patch or a 3.5 cm x 3.5 cm patch, respectively, without skin damage evidence.

Pharmacotherapy for tobacco dependence

Pharmacotherapy can provide effective treatment of tobacco dependence and withdrawal, and thereby facilitate efforts to achieve and sustain tobacco abstinence. Currently approved medications for smoking cessation are nicotine replacement medications (NRT), including nicotine patch, gum, lozenge, sublingual tablet, inhaler and nasal spray, the antidepressant bupropion, and the nicotinic partial agonist varenicline. This review discusses the pharmacological basis for the use of these medications, and the properties that might contribute to their efficacy, safety, and abuse liability. The review also discusses how pharmacological principles can be used to improve existing medications, as well as assist in the development of new medications.

[Role of tobacco use on the incidence of depression in the SUN cohort study]

BACKGROUND AND OBJECTIVE

Several investigations, most of them cross-sectional, have analyzed the association between smoking and depression, but there are not enough evidences to establish the direction of the association. Our objective was to prospectively assess the association between smoking habit and depression incidence in the SUN (Seguimiento Universidad de Navarra) cohort.

SUBJECTS AND METHOD

Dynamic cohort study (recruitment permanently open) based on 8,556 graduate participants where depression incidence was ascertained during 6 years of follow-up. Depression was defined as the presence of a self-reported physician diagnosis and/or use of antidepressant medication in at least one of the 2-year, 4-year or 6-year follow-up questionnaires. The association between smoking and depression incidence was estimated through the calculation of hazard ratios (HR) and their 95% confidence intervals (CI) using Cox regression models (proportional hazards).

RESULTS

The mean follow-up period was 47.4 months. One hundred and ninety participants initially free of depression reported a physician diagnosis of depression during follow-up. A significantly higher risk was found for smokers (HR = 1.39; 95% CI, 1.00-1.93) when they were compared to non smokers, whereas an inverse association was found for ex-smokers who had quit smoking more than 10 years ago (HR = 0.42; 95% CI, 0.19-0.94).

CONCLUSIONS

This study supports, with a prospective design, an increased risk of depression associated to smoking.

Diretrizes para cessação do tabagismo - 2008

Estas diretrizes constituem uma ferramenta atualizada e abrangente para auxiliar o profissional de saúde na abordagem do tabagista, recomendando atitudes baseadas em evidências clínicas como a melhor forma de conduzir cada caso. De forma reduzida e mais objetiva possível, o texto final foi agrupado em dois grandes itens: Avaliação e Tratamento. Os dois itens apresentam comentários e níveis de recomendação das referências utilizadas, bem como algumas propostas de abordagem, como por exemplo, redução de danos, em situações específicas ainda pouco exploradas, como recaídas, tabagismo passivo, tabagismo na categoria médica e uso de tabaco em ambientes específicos.

Smoking behavior postmyocardial infarction among ENRICHD trial participants: cognitive behavior therapy intervention for depression and low perceived social support compared with care as usual

INTRODUCTION

Patients with cardiovascular disease who stop smoking lower their risk of subsequent morbidity and mortality. However, patients who have suffered a myocardial infarction (MI) are more likely to be depressed than the general population, which may make smoking cessation more difficult. Poor social support may also make smoking cessation more difficult for some patients. This study examines the effect of cognitive behavior therapy (CBT) for depression, low perceived social support or both on smoking behavior in post-MI patients.

METHODS

Participants were 1233 patients with a history of smoking enrolled in the Enhancing Recovery in Coronary Heart Disease Patients (ENRICHD) trial who provided 7-day point-prevalence smoking behavior information at baseline and at two or more follow-up assessments. The ENRICHD trial enrolled post-MI patients with depression, low perceived social support or both. Participants were randomly assigned to either CBT intervention or usual care. We used mixed effects models to accommodate data from multiple smoking point-prevalence measures for each individual participant.

RESULTS

CBT did not significantly reduce post-MI smoking across all intervention patients with a history of smoking. However, CBT did reduce post-MI smoking among the subgroup of depressed patients with adequate perceived social support (OR, 0.68; 95% CI, 0.47-0.98).

CONCLUSION

CBT for depression without more specific attention to smoking cessation may have little overall value as a strategy for helping post-MI patients refrain from smoking. However, use of CBT to treat depression may have the gratuitous benefit of reducing smoking among some post-MI patients.

Novel pharmacological approaches for treating tobacco dependence and withdrawal: current status

Increasing the diversity and availability of medications for the treatment of tobacco dependence and/or withdrawal, to aid in the achievement of smoking cessation, is crucial to meet the diverse needs of tobacco users. Despite a general awareness that smoking is harmful and widespread interest in smoking cessation, nearly 50 million adults in the US and 1.3 billion worldwide continue to smoke. Nicotine replacement therapies are effective in the treatment of tobacco dependence and withdrawal, but do not meet the needs of all tobacco users. Improvement of tobacco dependence and/or withdrawal treatments is likely to rely on novel pharmacological approaches that include new chemical entities and new formulations of current drugs. In addition, new indications for treating tobacco dependence and withdrawal show promise for reducing tobacco use and associated disease. This article focuses on a range of novel pharmacological approaches for the treatment of tobacco dependence and/or withdrawal, including oral and pulmonary nicotine delivery and the following non-nicotinic medications: antidepressants, an alpha4beta2 nicotine partial agonist, an alpha2-noradrenergic agonist, cytochrome P450 (CYP) 2A6 inhibitors, opioid antagonists and GABAergic medications. In addition to existing medications, this article addresses novel medications in the clinical development stage and those that have been evaluated previously. Novel medications in the clinical development stage include at least three nicotine vaccines and the cannabinoid receptor acting drug rimonabant. Medications evaluated previously include lobeline, mecamylamine and an anticholinergic drug regimen comprising atropine, scopolamine and chlorpromazine. Having not been approved by major drug regulatory authorities for the treatment of tobacco dependence and/or withdrawal, these medications have been evaluated in an experimental capacity.

Stroke prevention: modifying risk factors

Risk factor modification remains as the principal aspect of care for stroke prevention. Understanding of risk factors has advanced and several options are now available to treat modifiable risk factors. However, effective treatment remains a challenging task in clinical practice. Prevention begins with awareness of risk factors by patients and clinicians. Risk factor assessment along with overall stroke risk estimation should be part of evaluation of patients with stroke, and used with careful clinical judgment. In this review, we discuss the impact of modifiable traditional vascular risk factors on ischemic stroke, interventions for stroke prevention, and evidence for early treatment of risk factors where available, as well as areas of research progress. Emphasis should be put on the education of patients, the community, and medical personnel. Future research in the field of genetic determinants of vascular risk factors and stroke will increase our understanding of the underlying mechanisms of cerebrovascular disease and likely result in development of new therapies and individualized programs for stroke prevention.

The effects of chronic versus acute desipramine on nicotine withdrawal and nicotine self-administration in the rat

RATIONALE

Nicotine withdrawal is characterized by depression-like symptomatology that may be mediated by dysregulations in norepinephrine transmission. These aversive aspects of nicotine withdrawal and the rewarding effects of nicotine play major roles in maintaining nicotine dependence.

OBJECTIVES

The aim of this work was to evaluate the effects of desipramine (DMI), a preferential norepinephrine reuptake inhibitor and antidepressant, on preclinical models of nicotine dependence in rats.

MATERIALS AND METHODS

A rate-independent current-intensity discrete-trial threshold intracranial self-stimulation procedure was used to assess brain reward function during nicotine withdrawal induced by cessation of nicotine infusion via subcutaneous osmotic mini pumps (3.16 mg/kg/day, base). Nicotine withdrawal was also measured by somatic signs of withdrawal. DMI was administered acutely (2 or 5 mg/kg, salt) during nicotine/saline withdrawal. In other naïve rats, chronic DMI treatment via mini pump (15 mg/kg/day, salt) began after 7 days of nicotine/saline exposure and continued during administration of nicotine/saline for 14 days and during nicotine/saline withdrawal. Additional rats acquired intravenous nicotine- or food-maintained responding, were prepared with DMI/vehicle-containing mini pumps, and self-administered nicotine or food during 12 days of DMI/vehicle exposure.

RESULTS

Acute DMI administration had no effect on threshold elevations observed in nicotine-withdrawing rats. Chronic DMI administration prevented the reward threshold elevations and the increased somatic signs of nicotine withdrawal. Although chronic DMI significantly decreased nicotine self-administration, it also decreased food-maintained responding.

CONCLUSIONS

The results suggest that norepinephrine reuptake inhibitors may be effective anti-smoking treatments that reduce the anhedonic depression-like and somatic components of nicotine withdrawal and may alter the rewarding effects of nicotine and food.

Therapeutic options and challenges for substances of abuse

Addiction to substances continues to be a significant public health concern in the United States. The following review of current pharmacological treatments discusses a range of substances: nicotine, alcohol, cocaine, and opioids. The goal is to provide an overview of currently available and new pharmacological treatments for substance use disorders, while also addressing the pharmacothera-peutic challenges remaining. The significant advances in pharmacotherapy have had limited utilization, however. For example, naltrexone for alcoholism is infrequently prescribed, buprenorphine for opiates still has relatively few qualified prescribers, and stimulants have no Food and Drug Administration-approved pharmacotherapy. These pharmacotherapies are needed, with the rate of even the relatively uncommon abuse of opiates now rising sharply.

Therapeutic drug monitoring of nortriptyline in smoking cessation: a multistudy analysis

Multiple, controlled clinical trials support the efficacy of nortriptyline as a smoking cessation agent. Although therapeutic plasma nortriptyline concentrations (PNCs) are known for the treatment of depression, little is known about PNCs in smoking cessation treatment. PNCs from three randomized, placebo-controlled smoking cessation trials (N=244) were analyzed both separately and pooled. PNCs normalized for dose and weight were associated with cigarettes per day and race, but not with sex or age. Greater smoking was associated with decreased normalized PNCs. In addition, both Asian and black populations had significantly higher normalized PNCs than the white populations. Weak and inconsistent associations between PNCs and self-reported side effects were observed. PNCs were linearly related to end of treatment and long-term biochemically verified smoking abstinence. Maximum therapeutic effects were observed over a range of plasma concentrations somewhat lower than those found effective for the treatment of depression.

Nicotinic Receptors: Role in Addiction and Other Disorders of the Brain

Nicotine, the addictive component of cigarette smoke has profound effects on the brain. Activation of its receptors by nicotine has complex consequences for network activity throughout the brain, potentially contributing to the addictive property of the drug. Nicotinic receptors have been implicated in psychiatric illnesses like schizophrenia and are also neuroprotective, potentially beneficial for neurodegenerative diseases. These effects of nicotine serve to emphasize the multifarious roles the drug, acting through multiple nicotinic acetylcholine receptor subtypes. The findings also remind us of the complexity of signaling mechanisms and stress the risks of unintended consequences of drugs designed to combat nicotine addiction.

Examining the clinical efficacy of bupropion and nortriptyline as smoking cessation agents in a rodent model of nicotine withdrawal

RATIONALE

At present, there is a lack of an established animal model to demonstrate the clinical efficacy of smoking cessation agents in the laboratory. The aim of this study was to compare the effects of the antidepressants bupropion and nortriptyline, clinically proven smoking cessation aids, within a rodent model of a nicotine withdrawal based on somatic measures.

MATERIALS AND METHODS

Male hooded Lister rats were chronically exposed to nicotine (3.16 mg kg1 day1) for 7 days via SC implanted ALZET osmotic minipumps. Animals were acutely pre-treated with bupropion (10, 30 or 60 mg/kg, IP) or nortriptyline (1.5, 4.7 and 15 mg/kg, IP), and nicotine withdrawal was precipitated by mecamylamine (1 mg/kg).

RESULTS

Precipitation of nicotine withdrawal led to an increase in somatic signs including body shakes, chews, eye blinks, foot licks, head shakes and ptosis. Bupropion dose-dependently decreased the total abstinence scores and reduced the occurrence of some individual somatic signs. Pre-treatment with 60 mg/kg bupropion did not result in a significant increase in total abstinence scores or individual somatic signs scores after mecamylamine challenge, compared to the mecamylamine control group, suggesting nicotine withdrawal is fully attenuated at this dose. Similarly, the highest dose of nortriptyline reduced total abstinence scores and some individual somatic signs to the level of the mecamylamine control group. However, nortriptyline was only effective at alleviating somatic measures of withdrawal at doses which also suppressed locomotor activity.

CONCLUSION

In concurrence with clinical findings proposing alleviation of withdrawal states as a possible mechanism of bupropion and nortriptyline's smoking cessation action, both drugs were found to ameliorate somatic signs of nicotine withdrawal in rodents.