A Randomized, Double-Blind, Placebo Controlled Study of l-Leucovorin in Combination With Trimethoprim / Sulfamethoxazole in the Therapy of Pneumocystis Carinii Pneumonia in Patients With the Acquired Immunodeficiency Syndrome

Inclusion Criteria Patients must have the following: Diagnosis of PCP. Fit the CDC definition of AIDS. Be receiving intravenous or oral trimethoprim / sulfamethoxazole (Bactrim, Septra) in doses of = or > 15mg/kg/day of the trimethoprim component. Be receiving = or < 48 hours of trimethoprim / sulfamethoxazole (TMP / SMX) prior to randomization. Must sign informed consent in accordance with FDA guidelines. Exclusion Criteria Co-existing Condition: Patients with the following conditions or symptoms are excluded: Cannot take oral medications. Require continued administration of anticonvulsant agents such as phenytoin, phenobarbital or primidone. Concurrent Medication: Excluded: Continued administration of anticonvulsant agents such as phenytoin, phenobarbital or primidone. Patients with the following are excluded: Cannot take oral medications. Require continued administration of anticonvulsant agents such as phenytoin, phenobarbital or primidone. Prior Medication: Excluded: > 48 hours of trimethoprim / sulfamethoxazole prior to randomization.