Nicotine replacement therapy (NRT) is a pharmacotherapy used commonly to help tobacco smokers quit smoking. All forms of NRT are demonstrably efficacious for this indication, and several forms, including transdermal nicotine (TN) are available over-the-counter in the United States. NRT is less efficacious in women than in men, although the specific reasons for this gender difference are unknown. NRT generally, and TN specifically, is thought to work, at least in part, by suppressing withdrawal symptoms in abstinent smokers. While TN-induced withdrawal suppression has been demonstrated, the degree to which this withdrawal suppression is influenced by smokers' gender is uncertain. The purpose of this acute laboratory study is to determine if TN-induced withdrawal suppression is influenced by smokers' gender.One hundred twenty eight overnight-abstinent smokers completed four, double-blind, randomized, 6.5-hour laboratory sessions in which further cigarette abstinence was required. Sessions differed by TN dose (0, 7, 21, or 42 mg). All sessions were double-blind and randomly ordered. Each session included regular assessment of subjective symptoms of nicotine/tobacco withdrawal, subjective effects of transdermal nicotine dose, psychomotor performance, heart rate and plasma nicotine level. Results from this laboratory study revealed clear nicotine dose-related effects for plasma nicotine and heart rate, symptoms of nicotine intoxication (e.g. Nausea, Lightheaded) and suppression of Urges to smoke and Craving. Many DSM IV nicotine/tobacco withdrawal symptoms did not show dose-related suppression (e.g. Irritability/frustration/anger, Anxious, Difficulty concentrating). Importantly, results from this study indicated that there were very few differences between men and women in nicotine-induced suppression of the nicotine/tobacco withdrawal syndrome. Future research addressing this important issue may benefit from focusing on a potential interaction between gender and other effects of TN (i.e., blunting the effects of a concurrently administered cigarette) and/or on other triggers for relapse (i.e., smoking-related stimuli).