Update on drug therapy for HIV and related infections in adults.

Antiretroviral therapy with zidovudine is indicated in patients with CD4 cell counts below 500 per mm3 (500 x 10(6) per L). Patients intolerant of zidovudine and those with advanced human immunodeficiency virus infection may benefit from newer antiretroviral agents, such as didanosine (ddl) or zalcitabine (ddC). Prophylactic therapy for Pneumocystis carinii pneumonia is indicated in patients with CD4 cell counts below 200 per mm3 (200 x 10(6) per L), in patients with CD4 cell counts less than 20 percent of the total lymphocytes and in patients with a prior history of P. carinii infection. In addition, prophylaxis is often initiated if thrush is present, even when CD4 cell counts are above 200. Trimethoprim-sulfamethoxazole is the drug of choice for Pneumocystis prophylaxis; aerosolized pentamidine is reserved for patients unable to tolerate trimethoprim-sulfamethoxazole. Oral candidiasis is treated with nystatin suspension, clotrimazole troches, ketoconazole or fluconazole, with fluconazole used for resistant or more invasive infection. Finally, acyclovir is used to treat herpes zoster or herpes simplex virus infection.