Double-blind co-operative trial to compare trimethoprim-sulfalene and co-trimoxazole in the treatment of lower respiratory tract infections.

Two fixed trimethoprim-sulfonamide combinations were compared in a clinical trial for their effectiveness and safety in the treatment of patients with acute lower respiratory tract infections (pneumonia, bronchopenumonia, purulent tracheobronchitis, ect.). 46 in-patients were randomly allocated to Kelfiprim (trimethoprim 250 mg + sulfalene (sulfamethopyrazine) 200 mg) or to co-trimoxazole (trimethoprim 320 mg + sulfamethoxazole 1600 mg) and were treated for 1-2 weeks under double-blind conditions. Assessment of effectiveness was based on daily follow-up of subjective and objective signs and symptoms, on changes in X-ray picture, and on microbiological and laboratory findings. Response to therapy was excellent or good in 86% of patients receiving Kelfiprim and in 79% of those given cotrimoxazole. Transient side-effects were observed in three patients under Kelfiprim (two allergic reactions and one G.I. complaint) and in one under co-trimoxazole (altered kidney function).