Pharmacotherapy for smoking cessation.

Nicotine dependence and the role of various pharmacotherapeutic adjuncts in the medical management of nicotine withdrawal and smoking cessation are reviewed. Nicotine has been shown to be the drug in tobacco that causes addiction. The nicotine withdrawal syndrome is primarily characterized by craving, irritability, frustration, anger, anxiety, poor concentration, restlessness, weight gain, and decreased heart rate. Pharmacotherapeutic interventions can be classified into four groups: therapy that (1) replaces nicotine, (2) antagonizes nicotine, (3) provides symptomatic treatment for nicotine withdrawal, and (4) deters smoking. Nicotine replacement therapy with nicotine polacrilex gum has had minimal effect on increasing-smoking cessation among patients seen in a general medical practice setting. It is most effective in nicotine dependent smokers when it is used concomitantly with behavioral or psychological counseling. Nicotine antagonist therapy with mecamylamine may be useful in recalcitrant cases of nicotine dependence. Clonidine, in both oral and transdermal forms, has been shown to be effective for reduction of symptoms and craving associated with smoking cessation. Research on using the tricyclic antidepressants imipramine and doxepin to promote smoking cessation by reducing withdrawal symptoms is in its preliminary phases. Lobeline, an alkaloid with effects similar to those of nicotine, is an FDA Category III drug (i.e., safe, but of unknown efficacy) and is available without prescription. Silver acetate chewing gum deters smoking by producing an unpleasant metallic taste on concomitant ingestion of the agent and tobacco. It is an FDA Category III drug and is available without prescription. Drugs used in therapy of nicotine withdrawal include nicotine replacements, nicotine antagonists, agents to lessen the symptoms of withdrawal, and smoking deterrents. None of the drugs is completely effective. Successful drug use for smoking cessation involves consideration of the psychological, as well as physiological, aspects of nicotine addiction.