INTRODUCTION: Little is known about behaviors linked to gamma hydroxybutyrate (GHB) morbidity. METHODS: We surveyed 131 GHB users, using logistic regression to test the associations between the high risk behaviors and hospital treatment for GHB (26 [20%] of subjects). RESULTS: Increased risk of GHB hospital treatment was associated with: co-ingestion of ethanol (OR 5.2; 95% CI 1.7-16), driving under the influence of GHB (OR 3.2; 95%, CI 1.3-7.8),use of GHB to treat withdrawal symptoms (OR 2.9; 95% CI 1.1-7.9), and co-ingestion of ketamine (OR 2.7; 95% CI 1.1-6.7). CONCLUSIONS: Targeted prevention activities could focus on selected high-risk behaviors.