To evaluate the safety, tolerability, and description of time to Pneumocystis carinii pneumonia (PCP) for long-term biweekly administration of 1 of 2 doses of aerosol pentamidine when used as a prophylactic agent in patients who have had one episode of AIDS-associated PCP.

Inclusion Criteria

Patients who have completed 16 treatments under Fisons study no. 87-71 entitled, "A Double-Blind Group Comparative Study To Evaluate the Safety and Effectiveness of Three Different Doses of Aerosol Pentamidine in the Prophylaxis of Pneumocystis Carinii Pneumonia in Patients With AIDS Post First Episode PCP." Detailed safety parameters must have been documented for 6 months.

• Patients must receive the first dose on this study within 2 weeks of their last dose under study no. 87-71.

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 patients with either of the following AIDS-defining O.I.'s at entry:
• Toxoplasmosis.
• Cryptococcosis.
• Pulmonary Kaposi's sarcoma.
• Asthma poorly controlled by medication.
• Receiving 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 patients with either of the following AIDS-defining O.I.'s at entry:
• Toxoplasmosis.
• Cryptococcosis.
• Pulmonary Kaposi's sarcoma.
• Unwilling to sign informed consent.
• Cannot cooperate with study procedures.
• Asthma poorly controlled by medication.
• Receiving active therapy for tuberculosis.

Active substance abuse.