OBJECTIVE To review published abstracts, case reports, and journal articles and evaluate data examining the use of systemic corticosteroids as adjuvant treatment for Pneumocystis carinii pneumonia (PCP) in patients with AIDS. METHODS Computerized online databases, peer-reviewed journals from January 1986 through September 1991, and personal communication with a National Institutes of Health correspondent. METHODS The authors identified 13 reports pertinent to this review. By author consensus, five studies were selected for analysis based on sample size, controlled study design, and clinical outcome measures. Recommendations of an expert panel from the National Institutes of Health and the University of California also are discussed. METHODS Data are presented based on the methodologic strength of the studies reviewed. Studies are assessed on sample size, inclusion criteria, comparative cohort populations, specific patient outcome measures, and statistical analysis. RESULTS Results of the study analysis support the use of systemic corticosteroids as early adjunctive therapy for AIDS patients with moderate-to-severe PCP who have an initial arterial oxygen partial pressure of less than 70 mm Hg or an alveolar-arterial gradient greater than 35 mm Hg on room air. Improved outcomes included decreased mortality, respiratory failure, and deterioration of oxygenation. Data evaluated have shown that adjuvant corticosteroid therapy is most effective when initiated within 72 hours of beginning specific antipneumocystis therapy. A small, but sometimes significant, increased rate of infection in steroid-treated patients was noted. CONCLUSIONS Based on the literature reviewed, early systemic adjuvant corticosteroid therapy can benefit patients with moderate-to-severe AIDS-related PCP. The steroid regimen used in the largest controlled trial and recommended by the expert panel is prednisone 40 mg bid (days 1-5), then 40 mg/d (days 6-10), then 20 mg/d (days 1-21).