Albendazole, marketed as Albenza (United States), Eskazole, Zentel, Andazol, and Alworm, is a benzimidazole drug used for the treatment of a variety of parasitic worm infestations. It is marketed in the U.S. by Amedra Pharmaceuticals, and by GlaxoSmithKline in international markets. Albendazole was first discovered at the SmithKline Animal Health Laboratories in 1972. It is a broad-spectrum anthelmintic, effective against roundworms, tapeworms, and flukes of domestic animals and humans. It is on the World Health Organization’s List of Essential Medicines, a list of the most important medications needed in a basic health system.