Inclusion Criteria

Concurrent Medication:

Allowed:

• Oral antiemetics.

Patients must have the following for inclusion:

• HIV positive by ELISA, p24 antigen or culture.
• Pneumocystis carinii pneumonia (PCP).
• Patients must have an (A-a) DO2 < 40 mmHg on room air.
• Willingness to sign an informed consent.

Prior Medication:

Allowed:

- Prophylaxis for Pneumocystis carinii pneumonia (PCP) with agents other than clindamycin and primaquine.

Exclusion Criteria

Concurrent Medication:

Excluded:

• Hematotoxic therapy, including zidovudine (AZT) or ganciclovir.

Patients with the following are excluded:

• History of allergy to clindamycin, lincomycin, or related drugs; or to primaquine or related drugs.
• Positive screen for G6PD deficiency, known NAD methemoglobin reductase deficiency, and/or known hemoglobin M abnormality.
• Concomitant conditions defined in Patient Exclusion Co-Existing Conditions.
• Any medical or social situation which, in the opinion of the investigator, would adversely affect participation in the study.
• Note:

Patients may be enrolled while G6PD screen is pending, but must be withdrawn if results are not known within 5 days after entry.

Prior Medication:

Excluded within 14 days of study entry:

• Systemic steroids at doses exceeding physiologic replacement or other investigational agents.
• Excluded within 6 weeks of study entry:
• Prior institution of any antiprotozoal therapy for the current episode of Pneumocystis carinii pneumonia or prophylaxis.

Patients must not have any of the following symptoms or diseases:

• History of allergy to clindamycin, lincomycin, or related drugs; or to primaquine or related drugs.
• Positive screen for G6PD deficiency, known NAD methemoglobin reductase deficiency, and/or known hemoglobin M abnormality.
• Diarrhea, defined as = or > 3 watery stools per day.
• Severe nausea and vomiting or other medical condition, such as ileus, that precludes oral therapy.
• Ventilator dependence or (A-a) DO2 = > 30 mm Hg.
• Any medical or social situation which, in the opinion of the investigator, would adversely affect participation in the study.
• Note:

Patients may be enrolled while G6PD screen is pending, but must be withdrawn if results are not known within 5 days after entry.