Valium, first marketed as Valium by Hoffmann-La Roche, is a benzodiazepine derivative drug. It possesses anxiolytic, anticonvulsant, sedative, skeletal muscle relaxant and amnestic properties. It is commonly used for treating anxiety, insomnia, seizures, alcohol withdrawal, and muscle spasms. It may also be used before certain medical procedures (such as endoscopies) to reduce tension and anxiety, and in some surgical procedures to induce amnesia.

http://en.wikipedia.org/wiki/Diazepam

Valium is in a group of drugs called benzodiazepines. It affects chemicals in the brain that may become unbalanced and cause anxiety. Valium is used in the management of anxiety disorders. It may also be used to treat agitation, shakiness, and hallucinations during alcohol withdrawal and to relieve certain types of muscle pain. Valium may also be used for other purposes not listed in this medication guide.

http://www.drugs.com/valium.html