The findings of this study have several implications. First, the prevalence of cannabis withdrawal symptoms among frequent cannabis users in the U.S. general population indicates a problem national in scope that is not limited to patients or individuals who willing to volunteer for inpatient laboratory studies. Given the projected increase in cannabis use in the coming decade, 4 the established increase in potency of the cannabis in general distribution in the U.S., 2 and evidence that higher potency increases the reward properties of cannabis, 27 the prevalence of cannabis withdrawal among users highlights the importance of understanding such withdrawal better. Second, the findings suggest that clinicians should be aware of the potential for cannabis withdrawal symptoms in frequent cannabis users, even if the primary drug is a different substance. Due to the common use of marijuana among patients in substance abuse treatment, the occurrence of cannabis withdrawal may need closer attention than previously believed. Post-hospital marijuana use predicts poor outcome of dependence on other substances, 48 and cannabis withdrawal symptoms may contribute to such poor outcome. Coverage of cannabis withdrawal
