GHB (gamma-hydroxybutyrate) refers to an anabolic steroid (synthetic derivatives of the male hormone testosterone), one type of club drugs being used by young people because of their euphoric, sedative, and bodybuilding effects. Like most steroids, GHB can cause high blood pressure, wide mood swings, liver tumors, and violent behavior. The drug's effects typically last up to 4 hours, depending on the dosage.