Information suggesting that zidovudine postexposure prophylaxis (PEP) reduces the risk of human immunodeficiency virus (HIV) transmission after occupational exposure to HIV-infected blood prompted the US Public Health Service to provide guidelines for the use of combination drug therapy for chemoprophylaxis after certain occupational exposures to HIV.1,2 Many health care workers (HCWs) worldwide may take PEP following occupational exposures to HIV.