DIAZEPAM (Valium®) is a benzodiazepine. Benzodiazepines belong to a group of medicines that slow down the central nervous system. Diazepam relieves anxiety and nervousness, and can be used for relaxation before surgery. It also can help relax certain muscles, and allows you to forget about unpleasant procedures, such as endoscopy. Diazepam also treats certain types of seizures (convulsions).