Long-Acting Sulfonamides in Urinary Tract Infections

Abstract

The pharmacological properties, side effects and clinical indications of five long-acting sulfonamides are compared and their relative clinical efficacy evaluated. Their adequate and sustained tissue-blood levels due to slow excretion rates, at low dosages, make them valuable and safe suppressive antibacterial drugs in the management of chronic urinary tract infections. In acute infections, and if obstructive uropathy, hematological abnormalities, hepatic or renal dysfunction co-exist, they are not indicated. In our experience, sulfadimethoxine has been safe and efficacious. Sulfamethoxypyridazine, although effective, is too toxic for general use. Under clinical investigation are AHR-857 used in 197 patients, sulfalene in 43 patients, and Ro 4-4393 in 12 patients. Ro 4-4393 is extremely long acting; 1 gm weekly maintains effective blood levels for seven days. These three drugs have been clinically quite effective and safe.