Gamma hydroxybutyrate (GHB) is a powerful central nervous system depressant. The number of individuals seeking treatment for GHB abuse has been steadily increasing in the United States. Currently, lorazepam and pentobarbital are two medications used to treat individuals who experience GHB-withdrawal symptoms. The purpose of this study is to describe the signs and symptoms of GHB withdrawal and to identify predictors of withdrawal severity. The study will also evaluate the safety and effectiveness of treatment with lorazepam versus pentobarbital for GHB detoxification.