Synthetic cannabinoid use is associated with severe problems, including psychosis, kidney failure, and death. Given that young adults are especially vulnerable to using synthetic cannabinoids, the current study sought to identify factors and consequences related to use within this population. 1140 undergraduates completed an online survey of synthetic cannabinoid use, consequences, and related constructs. The prevalence of lifetime synthetic cannabinoid use was 7.9% (n = 90), 15.6% (n = 13) of which were regular users, meaning they used once a year or more often. Synthetic cannabinoid users reported multiple adverse effects (e.g., anxiety, paranoia, tachycardia, lightheadedness) and 16.7% (n = 15) of users said they considered or did go to the Emergency Room while using synthetic cannabinoids. In the entire sample, participants believed their friends (t = 18.3, p < .001) and students in general (t = 46.0, p < .001) use synthetic cannabinoids more than they do. Natural cannabis users were associated with increased odds of having tried synthetic cannabinoids than those who had never used natural cannabis, OR = 7.63 (4.44 to 13.14) p < .0001, and 92.2% (n = 83) of synthetic cannabinoid users reported lifetime use of natural cannabis. Common reasons for use were legality, not appearing on drug tests, and availability, not that students enjoyed using synthetic cannabinoids or thought they were safe to use. Synthetic cannabinoid use is associated with a variety of negative consequences. The data also supports a strong link between natural cannabis use and synthetic cannabinoid use. Natural cannabis users appear to be a high-risk group for using synthetic cannabinoids. There are multiple negative effects associated with synthetic cannabinoid use and reasons for use relate to convenience vs. enjoyment. Data have important implications for prevention and treatment efforts.