Since the early 1980s, investigators have been reporting that adolescent smokers felt "dependent" on cigarettes and that adolescents trying to quit smoking experienced the same withdrawal symptoms observed in adult quitters, including restlessness, insomnia, increased appetite and weight gain, irritability or anger, depression, craving for cigarettes, and trouble concentrating. We hypothesized that most of these symptoms might be attributed to adolescence itself. To investigate this hypothesis, we examined the prevalence of these seven "adult" withdrawal symptoms in a population of adolescent former smokers and never-smokers. Participants were high school students in Houston, Texas, participating in a nested, group-randomized control group study designed to estimate the impact of a CD-ROM intervention for smoking prevention and cessation. We measured differences in symptoms frequency between never-smokers and former smokers, matched in a 2:1 ratio on sex and race/ethnicity, and differences in symptoms among former smokers as a function of time since final quit attempt and prior level of smoking. Only former heavy smokers have shown significantly higher prevalence of withdrawal symptoms compared with never-smokers. Of the seven symptoms assessed, only craving incrementally increased with the intensity of smoking. Overall the individual withdrawal symptoms did not effectively differentiate between 112 never-smokers and 34 former lighter smokers (persons who used to smoke less than "a few cigarettes on most days"). Withdrawal symptoms can reliably differentiate former heavy smokers from light smokers and never-smokers, among adolescents. Because most adolescents tend to be lighter smokers, future tobacco use and cessation studies should interpret adult withdrawal symptoms among adolescents with caution.