Topiramate-induced neuromodulation of cortico-mesolimbic dopamine function: a new vista for the treatment of comorbid alcohol and nicotine dependence?

Protective effects of forced exercise against topiramate-induced cognition impairment and enhancement of its antiepileptic activity: molecular and behavioral evidences

Propose/aim of study: Forced exercise can act as a neuroprotective factor and cognitive enhancer. The aim of the current study was to evaluate the effects of forced exercise on topiramate (TPM) induced cognitive impairment and also on TPM anti-seizure activity and neurodegeneration status after seizure.Material and method: Forty adult male rats were divided into four groups receiving normal saline, TPM (100 mg/kg), TPM in combination with forced exercise and forced exercise only respectively for 21 days. MWM test, and PTZ induced seizure were used and some oxidative, inflammatory and apoptotic biomarkers were measured for assessment of experimental animals.Results: Forced exercise in combination with TPM could abolish the TPM induced cognitive impairment and potentiates its anti-seizure activity. Also forced exercise in combination with TPM decreased malondialdehyde (MDA), tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β) and Bax protein, while caused increase in superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR) activities after PTZ administration.Conclusion: It seems that forced exercise could act as an adjunct therapy with TPM for management of induced cognitive impairment and can also potentiate TPM antiepileptic and neuroprotective effects.

Aripiprazole and topiramate, alone or in combination, block the expression of ethanol-induced conditioned place preference in mice

BACKGROUND

Ethanol is the most largely consumed drug in the world. Because of its complex mechanisms of action, studies suggest that the combination of drugs with distinct pharmacological effects may be a promising alternative for treating ethanol use disorder. In the present study, we aimed to investigate the effects of topiramate, alone and in combination with aripiprazole, on ethanol-induced conditioned place preference (CPP).

METHODS

Adult male mice were conditioned with ethanol (1.8 g/kg, i.p.) in the conditioned place preference (CPP) apparatus. Animals were then treated with vehicle, topiramate (2.5, 5 or 10 mg/kg, i.p.), aripiprazole (0.025, 0.05, 0.075 or 0.1 mg/kg, i.p.) or a combination of subthreshold doses of topiramate and aripiprazole (5 and 0.075 mg/kg, respectively) in the ethanol-paired compartment for 8 consecutive days. The expression of ethanol-induced CPP was then evaluated during a drug-free test performed 24 h after a re-exposure to ethanol in the ethanol-paired compartment.

RESULTS

Treatment with 10 mg/kg topiramate or 0.1 mg/kg aripiprazole blocked the expression of ethanol-induced CPP. Combined treatment with 5 mg/kg topiramate and 0.075 mg/kg aripiprazole, doses that alone were not effective, also blocked the expression of CPP to ethanol.

CONCLUSIONS

Topiramate and aripiprazole, alone or in combination, blocked the expression of ethanol-induced CPP. By showing that a combination of lower, subthreshold doses or topiramate and aripiprazole was effective in blocking the conditioned reinforcing properties of the ethanol-paired environment in mice, our current findings provide important insights into the therapeutic use of these drugs in ethanol use disorder.

Impulsiveness as a moderator of amphetamine treatment response for cocaine use disorder among ADHD patients

BACKGROUND

Amphetamines are a first-line treatment for ADHD and have shown promise for the treatment of cocaine use disorder (CUD), both alone and with comorbid ADHD. Impulsiveness is a key aspect of both ADHD and substance use disorders. We sought to understand the role of baseline impulsiveness in the treatment of comorbid CUD and ADHD.

METHODS

In a post hoc analysis (N = 76) of a 14-week, double-blind, randomized, placebo-controlled trial of mixed amphetamine salts-extended release (MAS-ER) for comorbid ADHD and CUD, we examined the relationship between treatment response and participants' baseline Barratt Impulsiveness Scale (BIS-11) score by comparing those with scores below versus above the median. In the original trial, participants received daily 60 mg MAS-ER, 80 mg MAS-ER, or placebo, in conjunction with cognitive behavioral therapy.

RESULTS

The odds of a cocaine-abstinent week over time were significantly greater in the high BIS group compared to the low BIS group, both when missing data was treated as missing (p = .0155; OR = 1.23, 95% CI: 1.13, 1.35 versus OR = 1.04, 95% CI: 0.95, 1.15) and when missing data was treated as cocaine-positive (p = .003; OR = 1.15, 95% CI: 1.06, 1.24 versus OR = 0.96, 95% CI: 0.88, 1.05).

CONCLUSIONS

The results show an association between higher within-group trait impulsiveness, as measured by the BIS-11, and response to MAS-ER for CUD in a cohort with comorbid ADHD. This result further demonstrates that impulsiveness is an important factor when considering treatment options for patients with CUD and that higher baseline impulsiveness may predict response to treatment with psychostimulants for CUD.

Role of the treatment environment in the effects of aripiprazole on ethanol-induced behavioral sensitization and conditioned place preference in female mice

BACKGROUND

Evidence suggests that aripiprazole, a partial dopamine D2 and serotonin 5-HT1A receptor agonist and 5-HT2A receptor antagonist, show significant efficacy in reducing alcohol use. We have previously demonstrated that treatment with aripiprazole blocked the reinstatement of cocaine-induced behavioral sensitization in a context-dependent manner, suggesting that the treatment environment may modulate the therapeutic effects of aripiprazole. The present study aimed to evaluate the effects of treatment with aripiprazole on ethanol-induced behavioral sensitization and conditioned place preference in female mice, and the role of the treatment environment in those effects.

METHODS

Adult female mice were either sensitized with ethanol injections in the open-field apparatus, or conditioned with ethanol in the conditioned place preference (CPP) apparatus. Animals were then treated with vehicle or 0.1 mg/kg aripiprazole paired to the test environment (open-field or CPP apparatus) or not (home-cage treatments) for 4 alternate days, and the subsequent expression of behavioral sensitization or CPP to ethanol was evaluated during or following an ethanol re-exposure, respectively.

RESULTS

Repeated treatment with aripiprazole attenuated the expression of ethanol-induced behavioral sensitization regardless of the treatment environment. Treatment with aripiprazole was only effective at preventing the reinstatement of ethanol-induced CPP when paired with the ethanol-associated environment, but not when administered in the home-cage.

CONCLUSIONS

The present findings corroborate previous studies suggesting the effectiveness of aripiprazole for the treatment of alcohol use disorder. Our results also point to an important role of the treatment environment in the therapeutic effects of aripiprazole in rodent models of ethanol abuse.

Randomized Clinical Trials Investigating Innovative Interventions for Smoking Cessation in the Last Decade

Every year, billions of dollars are spent treating smoking and related conditions, yet smoking-related morbidity and mortality continue to rise. There are currently only three FDA-approved medications for smoking cessation: nicotine replacement therapy, bupropion, and varenicline. Although these medications increase abstinence rates, most individuals relapse following treatment. This chapter reviews clinical trials published within the past 10 years investigating novel smoking cessation pharmacotherapies. Among these pharmacotherapies, some showed promising results, such as cytisine and endocannabinoid modulators, whereas others failed to produce significant effects. More research is needed to develop drugs that produce higher rates of long-term abstinence and to determine which subgroups of patients benefit from a given treatment.

Extended release mixed amphetamine salts and topiramate for cocaine dependence: A randomized clinical replication trial with frequent users

BACKGROUND

Cocaine use disorder (CUD) remains a substantial public health problem with no clearly effective pharmacotherapy available. In a prior trial, combined amphetamine and topiramate treatment significantly reduced cocaine use among individuals demonstrating the most frequent use at baseline. This trial targeted such frequent users.

METHODS

A double-blind, randomized placebo-controlled trial, testing the combination of mixed amphetamine salts extended-release (MAS-ER) and topiramate or placebo over a 12-week medication phase was conducted. The two-site outpatient trial included 127 adults (96 males) with CUD using at least 9 days in the prior month. MAS-ER was titrated to a maximum dose of 60 mg/day and topiramate to a maximum dose of 100 mg twice/day. The primary outcome was the proportion of individuals who achieved three consecutive abstinent weeks at the end of the study (EOS) as measured by urine toxicology and self-report.

RESULTS

The proportion of participants achieving three abstinent weeks at the EOS was significantly (P = .03) larger in the treatment (14.1%) compared to the placebo group (0.0%), while controlling for baseline cocaine use, sex, current alcohol use disorder, and site. Of note, due to conservative cardiac safety-parameters a considerable number of individuals in the treatment group were discontinued from study medication (20.3%).

CONCLUSIONS

While these findings provide further evidence that the combination of MAS-ER and topiramate is efficacious in promoting abstinence in CUD adults with frequent use it remains possible that the combination treatment is no more effective than either treatment alone. Despite this, the study provides a valuable "proof of concept."

Pilot investigation: randomized-controlled analog trial for alcohol and tobacco smoking co-addiction using contingency management

Contingency management (CM) is associated with decreases in off-target drug and alcohol use during primary target treatment. The primary hypothesis for this trial was that targeting alcohol use or tobacco smoking would yield increased abstinence in the opposite, nontargeted drug. We used a 2 [CM vs. noncontingent control (NC) for alcohol]×2 (CM vs. NC for smoking tobacco) factorial design, with alcohol intake (through urinary ethyl glucuronide) and tobacco smoking (through urinary cotinine) as the primary outcomes. Thirty-four heavy-drinking smokers were randomized into one of four groups, wherein they received CM, or equivalent NC reinforcement, for alcohol abstinence, smoking abstinence, both drugs, or neither drug. The CM for alcohol and tobacco group had only two participants and therefore was not included in analysis. Compared with the NC for alcohol and tobacco smoking group, both the CM for the tobacco smoking group [odds ratio (OR)=12.03; 95% confidence interval (CI): 1.50-96.31] and the CM for the alcohol group (OR=37.55; 95% CI: 4.86-290.17) submitted significantly more tobacco-abstinent urinalyses. Similarly, compared with the NC for the alcohol and tobacco group, both the CM for smoking (OR=2.57; 95% CI: 1.00-6.60) and the CM for alcohol groups (OR=3.96; 95% CI: 1.47-10.62) submitted significantly more alcohol-abstinent urinalyses. These data indicate cross-over effects of CM on indirect treatment targets. Although this is a pilot investigation, it could help to inform the design of novel treatments for alcohol and tobacco co-addiction.

Topiramate increases the rewarding properties of cocaine in young-adult mice limiting its clinical usefulness

RATIONALE

Topiramate is an anticonvulsant drug which has been evaluated as a therapeutic option for the treatment of cocaine addiction during the last decade.

OBJECTIVES

The purpose of this study was to evaluate the effects of topiramate on the reinforcing actions of cocaine. To this aim, the topiramate-mediated regulation of acquisition and extinction phases of the cocaine conditioned place preference (CPP) was assessed in young-adult mice using three experimental designs.

METHODS

Topiramate (50 mg/kg, p.o.) was given as follows: (1) during cocaine (1 and 25 mg/kg, i.p.) conditioning sessions (4 days) and cocaine (25 mg/kg) post-conditioning session; (2) 2 weeks before and during cocaine conditioning (25 mg/kg); and (3) during extinction of CPP induced by cocaine (25 mg/kg). In the first experimental design, changes in tyrosine hydroxylase (TH) and dopamine transporter (DAT) gene expressions were measured in the ventral tegmental area (VTA).

RESULTS

Topiramate significantly increased cocaine-induced CPP and delayed or failed to produce extinction after the first cocaine reinstatement extinction in the first and second experiments. Furthermore, treatment with topiramate after place conditioning blocked the extinction of cocaine-induced CPP. TH and DAT gene expression in the VTA was significantly lower both with topiramate alone and in combination with cocaine compared with animals receiving only cocaine.

CONCLUSIONS

These findings suggest that topiramate increases the rewarding properties of cocaine, at least in part, by regulating dopaminergic signaling in the mesolimbic circuit. Consequently, the results of this study do not support the use of topiramate for the treatment of problems related to cocaine dependence.

HIGHLIGHTS

• Topiramate increases the rewarding properties of cocaine in CPP • Topiramate alters dopaminergic signaling in the mesolimbic circuit • Topiramate delays the extinction of cocaine-induced CPP • TH and DAT gene expression in the VTA decreases with topiramate and/or with cocaine • Results show that it should limit the use of topiramate in cocaine-dependent subjects.

Tolerance to Ethanol or Nicotine Results in Increased Ethanol Self-Administration and Long-Term Depression in the Dorsolateral Striatum

Ethanol (EtOH) and nicotine are the most widely coabused drugs. Tolerance to EtOH intoxication, including motor impairment, results in greater EtOH consumption and may result in a greater likelihood of addiction. Previous studies suggest that cross-tolerance between EtOH and nicotine may contribute to the abuse potential of these drugs. Here we demonstrate that repeated intermittent administration of either EtOH or nicotine in adult male Sprague Dawley rats results in tolerance to EtOH-induced motor impairment and increased EtOH self-administration. These findings suggest that nicotine and EtOH cross-tolerance results in decreased aversive and enhanced rewarding effects of EtOH. Endocannabinoid signaling in the dorsolateral striatum (DLS) has been implicated in both EtOH tolerance and reward, so we investigated whether nicotine or EtOH pretreatment might modulate endocannabinoid signaling in this region. Using similar EtOH and nicotine pretreatment methods resulted in increased paired-pulse ratios of evoked EPSCs in enkephalin-positive medium spiny neurons in DLS slices. Thus, EtOH and nicotine pretreatment may modulate glutamatergic synapses in the DLS presynaptically. Bath application of the CB1 receptor agonist Win 55,2-212 increased the paired-pulse ratio of evoked EPSCs in control slices, while Win 55,2-212 had no effect on paired-pulse ratio in slices from either EtOH- or nicotine-pretreated rats. Consistent with these effects, nicotine pretreatment occluded LTD induction by high-frequency stimulation of the corticostriatal inputs to the dorsolateral striatum. These results suggest that nicotine and EtOH pretreatment modulates striatal synapses to induce tolerance to the motor-impairing effects of EtOH, which may contribute to nicotine and EtOH coabuse.

Effects of naltrexone plus topiramate on ethanol self-administration and tyrosine hydroxylase gene expression changes

The purpose of this study was to evaluate the effects of naltrexone (0.7 mg/kg) and/or topiramate (25 mg/kg) on ethanol consumption and the motivation to drink in an oral-operant conditioning paradigm in C57BL/6 mice. Subsequent real-time polymerase chain reaction (PCR) experiments were performed to analyze gene expression changes in tyrosine hydroxylase (TH) in the ventral tegmental area (VTA). The administration of naltrexone significantly reduced ethanol consumption and the motivation to drink during the different stages of the experiment, whereas the treatment with topiramate resulted in a much lower effect. Interestingly, the administration of naltrexone plus topiramate reduced ethanol consumption markedly compared with single-drug treatment. The water self-administration paradigm was also performed using the same drugs and no differences were found between treatment groups. Real-time PCR analyses revealed that naltrexone significantly normalized the increase of TH gene expression in the VTA induced by ethanol, whereas the administration of topiramate did not produce any significant effect. In the ethanol self-administration procedure, the combination of both drugs further reduced TH gene expression, reaching statistical significance compared with the vehicle, naltrexone or topiramate groups. Taken together, these findings indicate that the administration of naltrexone plus topiramate further reduced ethanol consumption and the motivation to drink in comparison with single-drug treatment. This action may be due, at least in part, to a greater decrease in TH gene expression in the VTA. These results suggest that the combination of both drugs deserves further exploration for the treatment of problems related to alcohol consumption.

Acute and chronic administration of a low-dose combination of topiramate and ondansetron reduces ethanol's reinforcing effects in male alcohol preferring (P) rats

Topiramate (a GABA/glutamate modulator) and ondansetron (a serotonin-3 antagonist) have shown promise as treatments for alcohol use disorders (AUDs), although efficacy is modest/variable for both medications. We recently showed in animal models of consumption and relapse that acute treatment with a combination of these medications was more efficacious than either alone. To determine whether the mechanism for its beneficial effects is through modulation of ethanol's reinforcing effects, we measured the effect of this combination in male alcohol preferring (P) rats (N = 22) responding for ethanol under a progressive-ratio (PR) schedule. Low doses, which either do not affect (ondansetron; 0.001 mg/kg) or only modestly affect (topiramate; 10 mg/kg) alcohol-related behaviors on their own, were selected in an attempt to maximize their combined efficacy while minimizing potential side effects. In addition to acute treatment (1 day), the effects of chronic administration (10 days) were examined in an attempt to model human treatment approaches. The effects of the combination were compared with the low dose of topiramate alone hypothesizing that the combination would be more efficacious than topiramate alone. Although both topiramate and the combination similarly reduced PR responding for ethanol following acute treatment and during the initial phase of chronic treatment (Days 1-5), after repeated administration (Days 6-10), only the combination produced a sustained reduction in ethanol-maintained responding. These results suggest an advantage of the combination over topiramate alone at producing a sustained reduction in ethanol's reinforcing effects following prolonged treatment, and lend further support for its use as a potential treatment for AUDs.

Topiramate for smoking cessation: a randomized, placebo-controlled pilot study

INTRODUCTION

Topiramate (TOP) blocks glutamate receptors and facilitates GABA (γ-aminobutyric acid) neurotransmission, effects that may facilitate smoking cessation. We compared the effects of behavioral counseling combined with (a) TOP, (b) TOP/nicotine patch (TOP/NIC), or (c) placebo (PLC) for smoking cessation.

METHODS

We conducted a 10-week randomized trial in which subjects and research personnel were blinded to TOP versus PLC but not to the TOP/NIC patch condition. In groups receiving TOP, the medication dosage was titrated gradually up to 200 mg/day. The smoking quit date (QD) was scheduled after 2 weeks of medication treatment. NIC (21 mg) was started on the QD in subjects randomized to the TOP/NIC condition. The main outcome measure was the end-of-treatment, 4-week continuous abstinence rate (CAR; biochemically confirmed).

RESULTS

Fifty-seven subjects were randomized to treatment. The 4-week CAR was 1 of 19 (5%) in the PLC group, 5 of 19 (26%) in the TOP group, and 7 of 19 (37%) in the TOP/NIC group (p = .056). Pairwise comparisons showed a difference between TOP/NIC and PLC (p = .042) and a nonsignificant difference between TOP and PLC (p = .18). The PLC group gained 0.37 lb/week, the TOP group lost 0.41 lb/week, and the TOP/NIC group lost 0.07 lb/week (p = .004). Pairwise comparisons showed a difference between TOP and PLC (p < .001) and between TOP/NIC and PLC groups (p = .035). Paresthesia was more frequent in subjects on TOP than PLC (p = .011).

CONCLUSIONS

TOP, alone or in combination with the NIC, resulted in a numerically higher quit rate than PLC and decreased weight. A larger, PLC-controlled trial is needed to confirm these findings.

Pregabalin- and topiramate-mediated regulation of cognitive and motor impulsivity in DBA/2 mice

BACKGROUND AND PURPOSE

Impulsivity is a core symptom in many neuropsychiatric disorders. The main objective of this study was to evaluate the effects of topiramate and pregabalin on the modulation of different impulsivity dimensions in DBA/2 mice.

EXPERIMENTAL APPROACH

The effects of acute and chronic administration of pregabalin (10, 20 and 40 mg·kg(-1) ) and topiramate (12.5, 25 and 50 mg·kg(-1) ) were evaluated in the light-dark box (LDB), hole board test (HBT) and delayed reinforcement task (DRT). α(2A) -Adrenoceptor, D(2) -receptor and TH gene expression were evaluated by real-time PCR in the prefrontal cortex (PFC), accumbens (ACC) and ventral tegmental area (VTA), respectively.

KEY RESULTS

Acute pregabalin administration showed a clear anxiolytic-like effect (LDB) but did not modify novelty-seeking behaviour (HBT). In contrast, topiramate produced an anxiolytic effect only at the highest dose, whereas it reduced novelty seeking at all doses tested. In the DRT, acute pregabalin had no effect, whereas topiramate only reduced motor impulsivity. Chronically, pregabalin significantly increased motor impulsivity and topiramate diminished cognitive impulsivity. Pregabalin decreased α(2A) -adrenoceptor and D(2) -receptor gene expression in the PFC and ACC, respectively, and increased TH in the VTA. In contrast, chronic administration of topiramate increased α(2A) -adrenoceptor and D(2) -receptor gene expression in the PFC and ACC, respectively, and also increased TH in the VTA.

CONCLUSIONS AND IMPLICATIONS

These results suggest that the usefulness of pregabalin in impulsivity-related disorders is related to its anxiolytic properties, whereas topiramate modulates impulsivity. These differences could be linked to their opposite effects on α(2A) -adrenoceptor and D(2) -receptor gene expression in the PFC and ACC, respectively.

Severity of drinking as a predictor of efficacy of the combination of ondansetron and topiramate in rat models of ethanol consumption and relapse

RATIONALE

Alcohol dependence is the third leading cause of preventable death in the USA. While single-agent pharmacotherapies have variable efficacy, medication combinations may produce additive effects by modulating multiple neural pathways.

OBJECTIVES

Here, we examined in animal models of ethanol consumption and relapse the combined effects of ondansetron (a serotonin-3 antagonist) and topiramate (a GABA/glutamate modulator), two medications with demonstrated efficacy for treating alcohol dependence, hypothesizing that their combination would produce a more efficacious response.

METHODS

The effects of acutely administered ondansetron (0-0.01 mg/kg) and topiramate (0-10 mg/kg) alone and in combination on ethanol consumption were examined in alcohol preferring (P) rats (N = 20) and in rats from their background strain (Wistars, N = 20) using a 24-h access free-choice paradigm. Next, we examined their ability to prevent an increase in ethanol consumption following a deprivation period (i.e., an animal model of relapse).

RESULTS

Whether administered alone or combined with ondansetron, topiramate produced a similar modest but persistent reduction in ethanol consumption. However, an analysis of efficacy by drinking level revealed that the combination was superior to topiramate alone in heavy-drinking P rats, but was without effect in lighter-drinking P rats and Wistar rats. Both topiramate alone and the combination blocked the alcohol deprivation effect in both Wistar and P rats with the combination tending to produce a greater decrease than topiramate alone.

CONCLUSIONS

The combination of ondansetron and topiramate may be a promising treatment for preventing relapse and for treating alcohol dependence in heavy-, but not lighter-drinkers.

Addressing tobacco use disorder in smokers in early remission from alcohol dependence: the case for integrating smoking cessation services in substance use disorder treatment programs

Despite the declining overall rate of cigarette smoking in the general population in the United States, the prevalence of smoking is estimated to be as high as 80% among treatment-seeking alcoholics. The serious adverse health effects of tobacco and heavy alcohol use are synergistic and recent evidence suggests that smoking slows the process of cognitive recovery following alcohol abstinence. In addition, substantial evidence shows that treatment for tobacco dependence does not jeopardize alcohol abstinence. In this paper, we focus on the impact and treatment implications of tobacco dependence among treatment-seeking alcoholics through a review of five areas of research. We begin with brief reviews of two areas of research: studies investigating the genetic and neurobiological vulnerability of comorbid tobacco and alcohol dependence and studies investigating the consequences of comorbid dependence on neurobiological and cognitive functioning. We then review literature on the effects of smoking cessation on drinking urges and alcohol use and the effectiveness of smoking cessation interventions with alcoholic smokers. Finally, we offer recommendations for research with an emphasis on clinical research for enhancing smoking cessation outcomes in this population.

Effects of topiramate or naltrexone on tobacco use among male alcohol-dependent outpatients

BACKGROUND

A high smoking prevalence has been registered among alcoholics. It has been pointed out that alcoholic smokers may have a more severe course and greater severity of alcoholism. This study aims at comparing smoking and non-smoking alcoholics in terms of treatment outcomes and verifying the efficacy of topiramate and naltrexone to decrease the use of cigarettes among alcoholic smokers.

METHODS

The investigation was a double-blind, placebo-controlled, 12-week study carried out at the University of São Paulo, Brazil. The sample comprised 155 male alcohol-dependent outpatients (52 non-smokers and 103 smokers), 18-60 years of age, with an International Classification of Diseases (ICD-10) diagnosis of alcohol dependence. After a 1-week detoxification period, the patients randomly received placebo, naltrexone (50mg/day) or topiramate (up to 300 mg/day). Only the alcoholic smokers who adhered to the treatment were evaluated with reference to the smoking reduction.

RESULTS

Cox regression analysis revealed that the smoking status among alcoholics increased the odds of relapse into drinking by 65%, independently of the medications prescribed, using the intention-to-treat method. Topiramate showed effectiveness to reduce the number of cigarettes smoked when compared to placebo among adherent patients (mean difference=7.91, p<0.01). There were no significant differences between the naltrexone group and the placebo group.

CONCLUSIONS

The results of this study confirm that the treatment is more challenging for smoking alcoholics than for non-smoking ones and support the efficacy of topiramate in the smoking reduction among male alcoholic smokers who adhered to the treatment.

Neurological comorbidity and epilepsy: implications for treatment

Epilepsy is a chronic condition that may be associated with several other diseases. In these cases, we should consider the following points: (1) antiepileptic drug (AED) treatment may positively or negatively affect comorbid disease, (2) drugs used for treatment of co-morbid disease may influence seizure threshold, (3) AED toxicity can be affected by a comorbid condition and (4) co-administration of AEDs with drugs used for treatment of comorbid conditions can be associated with clinically relevant drug-drug interactions. In this article, we discuss problems that are usually encountered when an appropriate AED treatment has to be selected in newly diagnosed epileptic patients who also have (an)other neurological disease(s). Comorbidity of epilepsy with cerebrovascular diseases, dementias, mental retardation, attention deficit and hyperactivity disorder, brain tumours, infections of the CNS, migraine, sleep disturbances (obstructive sleep apnoea syndrome), substance abuse and multiple sclerosis is discussed.

Topiramate may modulate alcohol abuse but not other compulsive behaviors in frontotemporal dementia: case report

Frontotemporal dementia (FTD) is an insidious presenile neurodegenerative disorder presenting with personality changes, compulsive behaviors, psychosis, apathetic, aberrant, and elated mood and behavior. No psychopharmacologic strategy has proven to be efficacious in the treatment of FTD yet. This is a case report of FTD in a 53-year-old male engineer whose alcohol abuse, but not other compulsive behaviors, responded to topiramate. Alcohol exerts reinforcing effects on cortico-mesolimbic dopamine pathways through the disinhibition of the inhibitory effects of gamma-amino-butyric acid-A neurons in the ventral tegmental area. Topiramate is a sulfamate-substituted fructopyranose derivative that may antagonize the reinforcing effects associated with the abuse liability of alcohol by modulation of cortico-mesolimbic dopamine function. On the basis of the mechanism of action of topiramate, we discuss the possible specificity of action of topiramate to control abusive drinking, but not to treat other clinical symptoms of FTD.

Topiramate does not alter nicotine or cocaine discrimination in rats

The effects of topiramate, a potential treatment for drug dependence, were evaluated in two groups of rats trained to discriminate the administration of either 0.4 mg/kg nicotine or 10 mg/kg cocaine from that of saline, under a fixed-ratio 10 schedule of food delivery. Topiramate (1-60 mg/kg, intraperitoneal) did not produce any nicotine-like or cocaine-like discriminative effects by itself and did not produce any shift in the dose-response curves for nicotine or cocaine discrimination. Thus, the ability to discriminate the effects of nicotine or cocaine does not appear to be altered by topiramate administration. Furthermore, topiramate, given either alone or in combination with nicotine or cocaine, did not depress rates of responding. These experiments indicate that topiramate does not enhance or reduce the ability of rats to discriminate the effects of nicotine or cocaine.

Preliminary evidence for gender-specific effects of topiramate as a potential aid to smoking cessation

AIMS

Study aims were threefold: (i) to determine the feasibility, potential efficacy and safety of topiramate as an aid to smoking cessation; (ii) to examine potential predictors of abstinence including gender; and (iii) to explore topiramate's effects on tobacco withdrawal and post-cessation weight gain.

DESIGN

Randomized, double-blind, placebo-controlled, 11-week clinical trial with a 6-week dosage titration period and 5 weeks of maintenance treatment.

SETTING

Single-site, out-patient, randomized clinical trial.

PARTICIPANTS

Thirty-eight adult male and 49 female chronic smokers who smoked an average of > 10 cigarettes per day and who were motivated to try to quit smoking.

INTERVENTION

Random assignment to receive either topiramate (n = 43) up to 200 mg daily in divided doses or placebo (n = 44) orally combined with brief counseling over an 11-week period.

MEASUREMENTS

Carbon monoxide (CO)-confirmed 4-week prolonged abstinence rate during weeks 8-11. Changes in tobacco withdrawal, body weight and safety parameters were also assessed.

FINDINGS

Overall, no significant increase in the prolonged abstinence rate was detected, but logistic regression analysis indicated significant gender-specific differences. Men treated with topiramate were nearly 16 times more likely to quit smoking than women on topiramate [37.5% versus 3.7%; odds ratio (OR) = 15.6; P = 0.016] and were roughly four times more likely to quit smoking than placebo-treated men (37.5% versus 13.6%; OR = 3.8; P = 0.098). Topiramate-treated men reported significantly lower tobacco withdrawal scores than both women taking topiramate and men on placebo. On average, male cessators on placebo gained 3.30 kg, whereas topiramate led to a 0.72 kg weight loss (P = 0.03). Study discontinuation rates due to adverse events (AEs) were significantly higher in the topiramate group (topiramate 23% versus placebo 2%). The most commonly reported AEs in the topiramate arm were paraesthesia, fatigue, difficulty with concentration/attention and nervousness.

CONCLUSIONS

Topiramate produced gender-specific effects on smoking cessation. Male smokers had markedly greater quit rates than female smokers and men were roughly four times more likely to quit smoking when treated with topiramate as compared to placebo. Topiramate was fairly well tolerated, although higher discontinuation rates were seen. Topiramate's triple effects aiding smoking abstinence, attenuating nicotine withdrawal and preventing post-cessation weight gain might make it a promising agent for treating tobacco addiction, at least in men.

Molecular pharmacodynamics, clinical therapeutics, and pharmacokinetics of topiramate

Topiramate (TPM; TOPAMAX) is a broad-spectrum antiepileptic drug (AED) that is approved in many world markets for preventing or reducing the frequency of epileptic seizures (as monotherapy or adjunctive therapy), and for the prophylaxis of migraine. TPM, a sulfamate derivative of the naturally occurring sugar D-fructose, possesses several pharmacodynamic properties that may contribute to its clinically useful attributes, and to its observed adverse effects. The sulfamate moiety is essential, but not sufficient, for its pharmacodynamic properties. In this review, we discuss the known pharmacodynamic and pharmacokinetic properties of TPM, as well as its various clinically beneficial and adverse effects.

Pharmacotherapy of dual substance abuse and dependence

The US FDA has approved a limited number of treatments for alcohol, nicotine and opioid dependence; however, no treatments for other abused drugs such as marijuana, cocaine or methamphetamine are approved. This review focuses on research into drug pharmacotherapies, particularly single-drug therapies, for substance abuse and dependence contributing to the most important dual substance use disorders (SUDs). Given the implications of poly-substance abuse, it is essential that clinicians and researchers be aware of potential pharmacotherapies for the treatment of dual SUDs.A substantial number of patients abuse more than one drug concurrently, complicating the treatment of SUD and leaving clinicians with few FDA-approved drug options for their patients. In this era of evidence-based medicine, such patients are typically treated with therapeutically proven medications, but in ways that are outside the scope of a drug's original indication by the FDA. Such 'off-label' prescribing has become an important therapeutic strategy for practitioners seeking treatments for other diseases in subpopulations such as paediatrics and gerontology or for medical conditions such as oncology or mental illness. Similarly, the information that most clinicians use to make their decisions for treating patients abusing multiple drugs stems from trials treating a single SUD, anecdotal experiences from their own practice or that of their colleagues, or single-case studies reported in the literature. The existing evidence suggests there are few treatments for SUDs that confer significant reductions in substance use across a broad patient population. Moreover, even fewer clinical efficacy trials have been conducted that provide evidence of therapeutic benefit for these drugs. Recognising the difficulty in making the proper drug choice for facilitating maximum treatment success, this review highlights the single drugs or drug combinations that show some potential for treating dual SUDs. This review finds strongest support for the use of disulfiram for treatment of alcohol and cocaine dependence (with or without concomitant methadone maintenance), baclofen for alcohol and cocaine dependence (but not opioid-dependent cocaine users), tiagabine for cocaine dependence in methadone-maintained patients, and topiramate for alcohol, nicotine and cocaine dependence. While ondansetron and olanzapine show some efficacy in treating alcohol and cocaine dependence, more research is needed to better delineate the subpopulation in which these drugs may provide their maximum effect.

Effects of topiramate on cue-induced cigarette craving and the response to a smoked cigarette in briefly abstinent smokers

RATIONALE

Clinical studies have shown that topiramate, an anticonvulsant medication, may be effective as a treatment for smoking cessation. However, less is known about topiramate effects on nicotine withdrawal and craving and its interactions with a smoked cigarette.

OBJECTIVES

The objective of this study was to investigate the effects of topiramate treatment on abstinence-related nicotine withdrawal, cue-induced cigarette craving, and the acute effects of a smoked cigarette.

MATERIALS AND METHODS

Fifteen female and 25 male cigarette smokers were randomly assigned to 9-day treatment with topiramate (final titration dose, 75 mg/day) or placebo. On the last day of treatment, after a 3-h smoke-free abstinence period, participants were evaluated for symptoms of nicotine withdrawal and then underwent cigarette and neutral cue reactivity testing. Thirty minutes after completing cue exposure testing, participants were then evaluated for the acute effects of a smoked cigarette. Cue reactivity and acute smoking measures included subjective ratings of cigarette craving and withdrawal and physiological measures of skin conductance and temperature, heart rate, and blood pressure. In addition, smoking topography was measured using a puff volume apparatus.

RESULTS

Topiramate treatment enhanced subjective ratings of withdrawal after the 3-h abstinence period and reduced pre-cue skin conductance levels. Cigarette cue exposure resulted in a moderate increase in craving, which was unaffected by treatment. Topiramate treatment enhanced the rewarding effects of a smoked cigarette, even while participants smoked less per puff and achieved lower plasma nicotine levels.

CONCLUSION

Results suggest that topiramate enhances both nicotine withdrawal and reward. These findings question the utility of topiramate treatment for smoking cessation.

Approaches to the development of medications for the treatment of methamphetamine dependence

BACKGROUND

Methamphetamine abuse has become an increasing problem in both the United States and globally with concomitant increases in adverse medical, social and environmental sequelae. Behavioral therapies have been used with some success to treat methamphetamine abusers and dependent individuals, but are not universally efficacious. Methamphetamine has a rich pharmacology that theoretically provides many opportunities for potential pharmacotherapeutic intervention. Nevertheless, there are no approved medications with an indication for treating methamphetamine abusers or addicts at this time.

AIM

To describe briefly how methamphetamine functions and affects function in brain and report how basic researchers and clinicians are attempting to exploit and exploiting this knowledge to discover and develop effective pharmacotherapies.

RESULTS

Scientifically based approaches to medications development by evaluating medications that limit brain exposure to methamphetamine; modulate methamphetamine effects at vesicular monoamine transporter-2 (VMAT-2); or affect dopaminergic, serotonergic, GABAergic, and/or glutamatergic brain pathways that participate in methamphetamine's reinforcing effects are presented.

CONCLUSION

The evidence supports the rationale that pharmacotherapies to decrease methamphetamine use, or reduce craving during abstinence may be developed from altering the pharmacokinetics and pharmacodynamics of methamphetamine or its effects on appetitive systems in the brain.

The CB1 cannabinoid receptor antagonist rimonabant chronically prevents the nicotine-induced relapse to alcohol

Preclinical and clinical research shows that the cannabinoid brain receptor type 1 (CB(1)) modulates alcohol- and nicotine-related behaviors. Throughout the nicotine-induced relapse to alcohol, the rats were pre-treated for 10 days with the CB(1) cannabinoid receptor antagonist rimonabant (0, 0.03, 0.3 and 3.0 mg/kg i.p.). In this condition, a long-lasting nicotine-induced relapse to alcohol was observed, and this effect was reversed in a dose-dependent manner with rimonabant. Surprisingly, rats that were not exposed to nicotine developed tolerance to the effects of rimonabant from the sixth day. Also, 3.0 mg/kg of rimonabant reduced the responses for sucrose. Evaluation in the Elevated Plus-Maze after nicotine treatment did not reveal anxiogenic effects. Finally, at the conclusion of rimonabant treatment, a rapid reinstatement of alcohol consumption was detected. These results suggest that rimonabant can prevent the relapse to alcohol, even when an interaction with nicotine exists-the most frequent situation in human alcohol abuse.

Acamprosate for the treatment of alcohol dependence

BACKGROUND

Both inpatient and outpatient treatment centers that focus solely on psychosocial therapies for the treatment of alcohol dependence have high relapse rates. Thus, extensive research has focused on the development of pharmacologic moieties to attenuate the craving for alcohol after acute alcohol detoxification. Three drug therapies are currently approved by the US Food and Drug Administration (FDA) for this purpose: disulfiram, naltrexone, and acamprosate. The latter was approved by the FDA in 2004.

OBJECTIVE

This article describes the pharmacologic properties and clinical usefulness of acamprosate for the treatment of alcohol dependence.

METHODS

Relevant information was identified through searches of MEDLINE (1966 to March 2005), International Pharmaceutical Abstracts (1970-2005), Current Contents (1996-2005), and Cumulative Index to Nursing and Allied Health Literature (1982-Week 2, 2004) using the key words acamprosate, alcohol dependence, and alcoholism (MeSH).

RESULTS

Acamprosate limited to randomized, controlled clinical trials yielded 33 hits in MEDLINE. Twenty-two articles were reviewed for efficacy end points, and 10 were reviewed for pharmacology and pharmacokinetics data. Acamprosate plus pharmacokinetics and pharmacodynamics yielded 19 hits, some of which were duplicates from the previously described search. Acamprosate plus meta-analysis (MeSH) yielded 5 hits, naltrexone plus meta-analysis (MeSH) yielded 9 hits, and disulfiram plus meta-analysis yielded 3 hits. The most recent review articles and their reference lists were assessed to ensure completeness of literature searches. Based on these searches, acamprosate is known to be an analogue of taurine and gamma-aminobutyric acid (GABA), 2 central nervous system neuromodulators. Acamprosate is thought to share some of the cellular actions of taurine affecting GABA and glutaminergic receptors in the nucleus accumbens, a brain region that may be responsible for the reinforcing effects received after alcohol consumption. Acamprosate is thought to also suppress excitation-induced calcium entry that results from chronic alcohol exposure, thereby altering the conformation of the N-methyl-d-aspartate receptors. The percentage of patients taking acamprosate who were completely abstinent throughout the different durations of the studies varied from approximately 18% to 61%, compared with 4% to 45% with placebo. Diarrhea was the most common adverse effect accompanying acamprosate therapy, and this was generally described as dose related and transient.

CONCLUSIONS

Acamprosate is associated with modest treatment effects. Its efficacy is similar to naltrexone, and the combination of acamprosate and naltrexone appears to be more efficacious than acamprosate alone, when combined with psychosocial interventions.

Topiramate in the treatment of compulsive sexual behavior: case report

BACKGROUND

Among the multiple mechanisms of action of topiramate, AMPA/kainate antagonism may be particularly interesting for the treatment of disorders characterized by conditioned cognitive and behavioral cue reactivity.

CASE PRESENTATION

We report the case of a patient consulting primarily for obesity and cue triggered snacking, who responded well on topiramate at doses up to 50 mg. Coincidentally he reported on an improvement of compulsive nonparaphilic sexual behaviors (consumption of prostitution), which was also strongly triggered by environmental cues. Both addictive behaviors (snacking and consumption of prostitution) reoccurred after discontinuation of topiramate and again responded reintroduction of the drug.

CONCLUSION

The present case report of topiramate's effect on comorbid obesity and nonparaphilic addiction could be interpreted as a further indication that topiramate acts on the common pathway underlying conditioned behaviors and seems to be a treatment of behavioral disorders associated with environmental cues.

Effects of topiramate in combination with intravenous nicotine in overnight abstinent smokers

RATIONALE

Topiramate, an anticonvulsant medication, may be effective as a treatment for alcohol and cocaine addiction. While a recent clinical study has demonstrated the potential utility of topiramate for smoking cessation in alcohol-dependent smokers, the effects of topiramate on tobacco addiction have not been systematically examined in humans.

OBJECTIVES

To determine topiramate's effects on acute physiological and subjective responses to intravenous (IV) nicotine in overnight abstinent smokers.

METHODS

Seven male and five female smokers participated in a double-blind, placebo-controlled, crossover study, which consisted of one adaptation and three experimental sessions. Before each session, participants were treated orally with either a single 25 or 50 mg topiramate dose or with placebo. Starting 2 h following the medication treatment, participants received an IV saline injection, followed by 0.5 and 1.0 mg/70 kg IV nicotine.

RESULTS

Topiramate treatment at 50 mg, compared to 25 mg or placebo, attenuated heart rate increases induced by nicotine. Topiramate, compared to placebo, enhanced the ratings of subjective effects from nicotine including "drug strength," "good effects," "head rush," and "drug liking." Topiramate treatment did not affect performance on the Stroop test.

CONCLUSIONS

These results suggest that topiramate may enhance the subjective effects of nicotine and attenuate the heart rate response to nicotine. While the exact mechanisms are unclear, enhancement of the dopaminergic system and attenuation of the noradrenergic system may mediate the topiramate's effects on the subjective and cardiovascular responses to nicotine, respectively. The utility of topiramate for smoking cessation needs to be examined further in controlled clinical trials.

Polymorphisms in the DBH and DRD2 gene regions and smoking behavior

The DRD2 TaqI A and DBH-1021 C/T polymorphisms were genotyped in smoking alcoholics (N = 100), non-alcoholic smokers (N = 120) and nonsmoking controls (N = 112). Alcoholic and non-alcoholic smokers presented a higher frequency of the DRD2 TaqI A1 allele (P = 0.04) than non-smoking controls. Individuals who had at least one DBH-1021 T allele smoked fewer cigarettes per day than CC homozygotes (P = 0.03). These results are coherent with the expected effects of these polymorphisms on dopaminergic function.

Topiramate augments the antipsychotic-like effect and cortical dopamine output of raclopride

Recent clinical studies have shown that the anticonvulsant drug topiramate may improve negative symptoms in schizophrenia when added to a stable regimen of neuroleptic medication. It has also been shown that addition of topiramate to neuroleptics might be beneficial in treatment-resistant schizophrenia. Clinically effective doses of antipsychotic drugs (APDs) have been found to suppress conditioned avoidance response behavior (CAR), a preclinical test of antipsychotic activity with high predictive validity, in rats. Therefore, we investigated the putative antipsychotic-like activity of topiramate when added to the selective dopamine (DA) D2 receptor antagonist raclopride, using the CAR model in the rat. Extrapyramidal side effect liability of the drug combination was evaluated in parallel by means of the catalepsy test. We also examined the effect of this drug treatment on DA release in the medial prefrontal cortex (mPFC) and the nucleus accumbens (NAC), using in vivo microdialysis in freely moving animals. Topiramate (40 mg/kg), while ineffective when given alone, significantly augmented the antipsychotic-like effect of raclopride (0.075 mg/kg) on CAR without any concomitant catalepsy. Addition of topiramate to rats treated with raclopride generated a large increase in DA output in the mPFC, whereas no additional effect on the raclopride-induced DA release in the NAC was obtained. These data support the adjunctive use of topiramate in schizophrenia to ameliorate negative symptoms and suggest that this treatment may increase the efficacy, but not the extrapyramidal side effect liability, of the APDs used.

Nicotine addiction and comorbidity with alcohol abuse and mental illness

The World Health Organization estimates that one-third of the global adult population smokes. Because tobacco use is on the rise in developing countries, death resulting from tobacco use continues to rise. Nicotine, the main addictive component of tobacco, initiates synaptic and cellular changes that underlie the motivational and behavioral alterations that culminate in addiction. Nicotine addiction progresses rapidly in adolescents and is most highly expressed in vulnerable people who have psychiatric illness or other substance abuse problems.

Novel pharmacotherapeutic targets for the management of drug addiction

Despite individual variation in the liability to the abuse of psychoactive substances, there is substantial commonality shared by drugs of abuse. The knowledge of these common mechanisms together with the continued elucidation of the neurobiological underpinnings of withdrawal symptoms, drug intake, craving, relapse, and co-morbid psychiatric associations are critically important for the development of new therapeutic strategies. The present review will focus on recent advances in the development of innovative pharmacotherapeutic agents, which should promote higher efficacy (abstinence, prevention of relapse, long-term recovery) and patient compliance, as well as improved safety profiles.

Expanding treatment of tobacco dependence

Nicotine dependence is the leading preventable cause of adult morbidity and mortality in the world. New research on the treatment of this disorder ranges from studies evaluating access to treatment to studies elucidating the molecular mechanisms of nicotine addiction. As our understanding of the neurobiology of tobacco addiction grows, the number of potential therapeutic targets by which we can intervene in this pernicious disorder also increases. This paper presents an overview of recent research trends in the treatment of tobacco dependence. We review several novel mechanisms of action that may serve as therapeutic targets for the pharmacologic treatment of tobacco dependence, including drugs that affect monamine oxidase, selective nicotinic receptors, glutamate and gamma-aminobutyric acid receptors, and the endocannabinoid system. For each of these therapeutic targets, we discuss medications in development that affect these pathophysiologic mechanisms.

Medications development: Successes and challenges

The National Institute on Drug Abuse has funded a medications program that has concentrated on the development of medications for opiate and cocaine dependence. Levomethadyl acetate (LAAM) and buprenorphine and buprenorphine/naloxone sublingual tablets were developed in conjunction with pharmaceutical partners and approved by the Food and Drug Administration. The remaining challenges for medications development for opiate dependence involves Phase IV studies in special populations, for example, pregnant opiate-dependent patients, and to translate neuroscience-based findings into treatments. Several marketed medications have shown initial efficacy to reduce cocaine use in well-controlled clinical trials. Disulfiram has been shown to reduce cocaine use in several clinical trials, while baclofen, modafinil, naltrexone, ondansetron, tiagabine, and topiramate have shown preliminary efficacy in initial clinical studies. Confirmatory studies of many of these medications is underway. More recently, the NIDA medications program has evaluated medications for their ability to reduce methamphetamine use. To date, no medications tested have shown efficacy to reduce methamphetamine use. Both marketed medications and investigational agents will be tested. Finally, NIDA has begun to test medications for efficacy to reduce cannabis use. Initial studies are underway. Both agonist and antagonist approaches will be evaluated. Additionally, medications will be tested in cannabis-dependent patients for the management of insomnia, withdrawal, and concurrent depression.

Development of medications for alcohol use disorders: recent advances and ongoing challenges

During the past decade, efforts to develop medications for alcoholism have burgeoned. Three agents, disulfiram, naltrexone and acamprosate, are now approved in a large number of countries. Although many patients have benefited from existing medications, their effects are moderate, and some alcoholics fail to respond to them. A host of new agents are currently under active investigation. Critical barriers must be overcome to ensure that future efforts in the development of medications for alcohol use disorders reach full fruition. These challenges include: establishing key targets for drug discovery; validating animal and human screening models; and developing biomarkers to help predict treatment success. In addition, it is important to formulate methodological and statistical strategies to efficiently conduct alcohol pharmacotherapy trials; to specify genetic and phenotypic patient characteristics associated with efficacy and safety for lead compounds; to forge productive alliances among governmental agencies, the pharmaceutical industry and academic researchers to further drug development; and, ultimately and perhaps most difficult, to engage the practitioner community to incorporate medications into the alcohol treatment process.

Pharmacotherapy and other treatments for cocaine abuse and dependence

PURPOSE OF REVIEW

This review examines progress being made in the treatment of cocaine abuse and dependence, with a particular focus on pharmacotherapies. Medications with apparently very different mechanisms of action have been reported to reduce cocaine use in controlled clinical trials in outpatient settings. This review will summarize the latest findings in this area.

RECENT FINDINGS

Of all the medications tested to date, disulfiram has demonstrated the most consistent effect to reduce cocaine use. Several medications have been reported to reduce cocaine use in double-blind, placebo-controlled clinical trials, namely baclofen, modafinil, tiagabine, and topiramate. All pharmacotherapy trials in cocaine-dependent patients include a behavioral therapy that is common to all participants. Consequently, these pharmacotherapy trials can be considered to evaluate whether the medication is adding to the effect of the behavioral therapy.

SUMMARY

Confirmatory clinical studies are necessary to replicate the initial efficacy findings for baclofen, modafinil, tiagabine, and topiramate. More research is needed in both cocaine and cocaine-alcohol dependent populations. Once confirmatory studies have been carried out, testing of rational medication combinations with different behavioral therapies is an obvious next step to increase the ability to manage cocaine dependence.

Effects of acute topiramate dosing on open field behavior in mice

Although topiramate (TPM) has been used to treat human disease, there are few studies of its effects on the behavior of animal models. Objective. This study aimed to assess the effect of acute TPM administration on the behavior of mice undergoing the open-field test. Method. The animals were divided in two groups: the treatment group (n = 10), which received 10 mg/kg TPM intraperitoneally, and the control group (n = 10), which received saline. 30 minutes after drug administration, the animals were assessed for 5 minutes in the open-field. The following parameters were analyzed: number of squares explored, immobility time, central area permanence time, peripheral apparatus permanence time, rearing frequency and time, grooming frequency and time, rearing frequency during the last minute, number of fecal boli, and estimated speed. Results. The treatment group had a higher number of squares explored (p = 0.02) and greater estimated speed (p = 0.01). Conclusion. The results suggest that acute TPM administration increases the locomotor activity of mice without interfering with learning, anxiety, stress, and exploratory behavior.