Withdrawal from nicotine dependence using mecamylamine: comparison of three-week and six-week dosage schedules.

Mecamylamine (MCL) has been shown to extinguish nicotine dependence in animals and produce smoking cessation in some humans. This study was done to determine if MCL may be more effective and have fewer side-effects when administered at low dosages over a six-week period than at high dosages given over a three-week period. Subjects in the high-dose, three-week group demonstrated significantly more reduction of nicotine intake as evidenced by self-report and presence of nicotine in urine although side-effects were more pronounced. Although MCL's numerous side-effects should limit its clinical use to recalcitrant smokers who have failed other types of treatment, its nicotine antagonist property indicates it can be an effective agent to withdraw some persons from nicotine dependence.