Intravenous drug use (IVDU) is the unlawful self-administration of a psychopharmacologically active substance by the intravenous route. Opioids such as heroin (diamorphine), buprenorphine (especially in France), and morphine (usually medicinal morphine sulphate ground into powder and suspended in partial solution) are the drugs most commonly taken intravenously. Amphetamine sulphate, cocaine, and increasingly crack cocaine (especially in Latin America) and short-acting benzodiazepines such as temazepam and lorazepam are also frequently injected. Single drug use is rare and many users will experiment with different compounds and may have comorbid alcohol abuse or dependency and major psychiatric disorders such as depression and schizophrenia or schizoaffective disorder.