Because safe, effective treatment for established viral hepatitis is not available, physicians need to be acquainted with recent advances in prophylaxis. Immune globulin (Gamastan, Gammar) is used for both preexposure and postexposure prophylaxis of hepatitis A, and side effects are rare. Two vaccines (Heptavax-B, Recombivax HB) are licensed for hepatitis B, one is a plasma-derived vaccine, the other a yeast-recombinant vaccine. Indirectly, these also control hepatitis D (delta agent), which needs hepatitis B virus to develop.