To evaluate and compare the safety, tolerability, and efficacy of biweekly administration of 1 of 3 doses of aerosol pentamidine when used as a prophylactic agent in patients who have recovered from their first episode of AIDS-associated Pneumocystis carinii pneumonia (PCP).

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.