The Safety and Effectiveness of Pentamidine in the Prevention of Pneumocystis Carinii Pneumonia (PCP) in Patients With AIDS Who Have Had PCP Before

Inclusion Criteria Concurrent Medication: Allowed: Zidovudine (AZT). Exclusion Criteria Co-existing Condition: Patients with the following are excluded: Requiring ongoing active therapy for an opportunistic infection (O.I.) at time of entry or those with either of the following AIDS-defining O.I.'s prior to entry: Toxoplasmosis. Cryptococcosis. Transfusion dependent (requiring blood transfusion more than once per month). The last transfusion cannot have been given within 7 days of study entry. Pulmonary Kaposi's sarcoma (KS). Asthma requiring medication. Active therapy for tuberculosis. Concurrent Medication: Excluded: Active therapy for tuberculosis. Patients with the following are excluded: Requiring ongoing active therapy for an opportunistic infection (O.I.) at time of entry or those with either of the following AIDS-defining O.I.'s prior to entry: Toxoplasmosis. Cryptococcosis. Transfusion dependent (requiring blood transfusion more than once per month). The last transfusion cannot have been given within 7 days of study entry. Pulmonary Kaposi's sarcoma (KS). Unwilling to sign informed consent. Cannot cooperate with study procedures. Asthma requiring medication. Prior Medication: Excluded within 30 days of study entry: Antiretrovirals other than zidovudine (AZT). Immunomodulating agents. Corticosteroids. Patients must: Have AIDS and recovered from their first episode of cytologically or histologically proven Pneumocystis carinii pneumonia (PCP). Be at least 2 weeks and no more than 24 weeks status post therapy for acute PCP. Have positive antibody to HIV by any federally licensed ELISA test kit, or confirmed Western blot test. Have adequate pulmonary function (vital capacity = or > 80 percent of predicted; forced expiratory volume (FEV), 1 s = or > 65 percent of total FEV; and corrected pulmonary diffusion capacity > 60 percent of predicted). Free of acute medical problems. Active substance abuse.