Pharmacotherapy for smoking cessation: pharmacological principles and clinical practice

Abstract

Strategies for assisting smoking cessation include behavioural counselling to enhance motivation and to support attempts to quit and pharmacological intervention to reduce nicotine reinforcement and withdrawal from nicotine. Three drugs are currently used as first line pharmacotherapy for smoking cessation, nicotine replacement therapy, bupropion and varenicline. Compared with placebo, the drug effect varies from 2.27 (95% CI 2.02, 2.55) for varenicline, 1.69 (95% CI 1.53, 1.85) for bupropion and 1.60 (95% CI 1.53, 1.68) for any form of nicotine replacement therapy. Despite some controversy regarding the safety of bupropion and varenicline, regulatory agencies consider these drugs as having a favourable benefit/risk profile. However, given the high rate of psychiatric comorbidity in dependent smokers, practitioners should closely monitor patients for neuropsychiatric symptoms. Second-line pharmacotherapies include nortriptyline and clonidine. This review also offers an overview of pipeline developments and issues related to smoking cessation in special populations such as persons with psychiatric comorbidity and pregnant and adolescent smokers.

Keywords: bupropion; clonidine; mental health; nicotine; pregnancy; varenicline.

Figure 1

Schematic presentation of plasma nicotine concentrations in venous blood of a smoker over a 24 h period (A) and in an abstinent smoker using nicotine patch (NP) and buccal/nasal absorption nicotine replacement products (B). Combination of NP with rapid, buccal/nasal absorption NRT leads to a higher area under the plasma nicotine concentration curve and peak nicotine concentrations. These result in more time spent above the craving/urge to smoke plasma nicotine concentration threshold and a better mimicking of self-titrated nicotine peaks. (With permission from Journal of Chronic Obstructive Pulmonary Disease, Reference Foulds et al. [26])