RANDOMIZED CONTROLLED TRIAL OF NICOTINE CHEWING-GUM

The effectiveness of 2 mg nicotine chewing-gum as an aid to stopping smoking was compared with a placebo containing 1 mg nicotine, but unbuffered, in a double-blind randomized trial. Of 58 subjects given the active gum, 27 (47%) were not smoking at 1-yr follow-up compared with 12 (21%) of the 58 subjects treated with placebo (P < 0.025). By the most stringent criterion of outcome, 18 (31%) subjects in the active treatment group and 8 (14%) in the placebo group had not smoked at all from the start of treatment of follow-up at 1 yr (P < 0.05). Subjects receiving the active gum experienced less severe withdrawal symptoms and rated their gum as more helpful than did the placebo group. Minor side effects were common, but only gastric symptoms were more frequent with the active gum. Subjects receiving active gum used it for longer than those receiving placebo, but most stopped using it within 6 mo., and only 4 (7%) developed longer-term dependence. The number of gums used daily correlated significantly with pretreatment blood nicotine concentrations in the active treatment group and with pretreatment cigarette consumption in the placebo group. A lower pretreatment blood nicotine value was the best predictor of success at 1 yr (P < 0.001) but there was no significant relation to cigarette consumption, sex and social class. The results clearly confirm the usefulness of nicotine chewing-gum as an aid to stopping smoking and imply a definite role for nicotine in cigarette dependence and withdrawal. Successful use of the gum requires careful attention to subjects'' expectations and clear instructions on how to use it.