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.