A Double-Blind Placebo-Controlled Group Comparative Study To Evaluate the Safety and Effectiveness of Aerosol Pentamidine in the Prophylaxis of Pneumocystis Carinii Pneumonia in Patients With AIDS Post First Episode PCP

Inclusion Criteria Concurrent Medication: Allowed: * Zidovudine (AZT). If AZT is started during the study, patients must have received = or \> 15 days of aerosol pentamidine before beginning AZT. Prior Medication: Allowed: * Zidovudine (AZT). If AZT began prior to study entry, patients must have received = or \> 15 days of AZT before beginning aerosol pentamidine. 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). * Uncontrolled asthma. * 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). * Uncontrolled asthma. Prior Medication: Excluded within 30 days of study entry: * Antiretroviral agents other than zidovudine (AZT). * Immunomodulating agents. * Corticosteroids. Active therapy for tuberculosis. Patients must: * Have AIDS and recovered from their first episode of 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 a Government-approved ELISA test kit, or confirmed Western blot test. * 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.