To compare parenteral versus inhaled pentamidine in patients with documented Pneumocystis carinii pneumonia (PCP) with AIDS.
Exclusion Criteria Co-existing Condition: Patients with the following are excluded: * Previous history of adverse reaction to pentamidine. * History of asthma. * Pulmonary Kaposi's sarcoma. Patients with the following are excluded: * Previous history of adverse reaction to pentamidine. * History of asthma. * Pulmonary Kaposi's sarcoma. * Inability to understand the consent procedure. All patients hospitalized at Cedars-Sinai Medical Center with AIDS and possible Pneumocystis carinii pneumonia (PCP) will be eligible. * Patients with HIV antibody or AIDS and a clinical presentation suggesting PCP are eligible.