DISEASE CHARACTERISTICS: Currently smoking at least 10 cigarettes per day Smoked regularly for the past year Motivated to use study medication More than 30 days since prior use of tobacco products other than cigarettes (e.g., smokeless tobacco, pipes, cigars, or snuff) No active chemical dependence of drug other than nicotine (e.g., alcohol, marijuana, cocaine, heroin, or other illicit drugs) within the past year