Medical patients (n = 315) who wished to quit smoking were randomly assigned in a double-blind manner to receive either nicotine or placebo gum. Subjects were advised to stop gum use by 4 months. Among abstinent smokers, 46% of those receiving nicotine gum and 17% of those receiving placebo gum used the gum beyond the recommended 4-month period. By 10 months after cessation 17% of quitters receiving nicotine gum and 6% receiving placebo gum were still using gum. Gradual reduction of nicotine gum did not result in withdrawal and cessation of nicotine gum did not increase the probability of relapse to smoking or weight gain. We conclude that use of nicotine gum is due, in part, to the effects of nicotine; however, long-term use is uncommon.