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

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.

Effectiveness of pharmacotherapy for smoking cessation: protocol for umbrella review and quality assessment of systematic reviews

BACKGROUND

In the long term, smoking cessation can decrease the risk of cancer, stroke, and heart attacks and improve overall survival. The aim of the proposed umbrella review is to summarize existing systematic reviews that assessed the effects of pharmacological interventions for smoking cessation and to evaluate the methodological quality of previously conducted systematic reviews.

METHODS

Databases such as the Cochrane Library, PubMed, MEDLINE, EMBASE, CINAHIL PsychINFO Web of Science, Conference Papers Index, Scopus, and Google Scholar will be used to retrieve reviews. Systematic reviews which included only randomized control trials will be considered in this review. The primary outcome will be prolonged abstinence from smoking for a minimum of 6 months follow-up, and the secondary outcome will be point abstinence rate from smoking of less than 6 months follow-up but more than 7 days. Methodological quality of the included reviews will be assessed using the Assessment of Multiple Systematic Reviews 2 (AMSTAR 2) tool, which contains 16 domains. Two authors will screen the titles and abstracts of all reviews obtained by the search strategy, assess the full text of selected articles for inclusion, and extract data independently. The quality appraisal will be also assessed by two authors (AM, CC) independently, and Cohen's Kappa statistic will be used to assess inter-ratter agreement. The findings of the study will be narrated qualitatively to describe the effect of different pharmacotherapy on smoking cessation.

DISCUSSION

The World Health Organization recommends treatment of tobacco dependence as one approach in its comprehensive tobacco control policy. To date, many trials and systematic reviews have been conducted to assess the effectiveness of pharmacotherapy for smoking cessation. Therefore, the findings of the umbrella review will improve clinical decision-making and be used as a baseline for future studies.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42017080906.

Tobacco use and cessation for cancer survivors: an overview for clinicians

Approximately 30% of all cancer deaths in the United States are caused by tobacco use and smoking. Cancers of eighteen sites have been causally linked to smoking, the most common of which are the lung, head and neck, bladder, and esophagus. While quit rates and quit attempt rates are relatively high shortly after a cancer diagnosis, the recidivism rates are also high. Therefore, screening, treating, and preventing relapse to tobacco use is imperative among patients with and survivors of cancer. To date, research has consistently shown that a combination of pharmacologic and behavioral interventions is needed to achieve the highest smoking cessation rates, with a recent emphasis on individualized treatment as a most promising approach. Challenges in health care systems, including the lack of appropriate resources and provider training, have slowed the progress in addition to important clinical considerations relevant to the treatment of tobacco dependence (eg, a high degree of comorbidity with psychiatric disorders and other substance use disorders). However, continued tobacco use has been shown to limit the effectiveness of major cancer treatments and to increase the risk of complications and of developing secondary cancers. The authors recommend that oncology providers screen all patients for tobacco use and refer users to specialized treatment when available. Alternatively, oncology clinicians can provide basic advice on tobacco use cessation and pharmacotherapy and/or referral to outside resources (eg, quitlines). Herein, the authors summarize the current knowledge on tobacco use and its treatment, with a focus on the related available evidence for patients with and survivors of cancer.