The sulfonamides are commonly used to treat or prevent acute systemic or local infections.

 

Disease syndromes treated with sulfonamides include actinobacillosis, coccidiosis, mastitis, metritis, colibacillosis, pododermatitis, polyarthritis, respiratory infections, and toxoplasmosis.

 

Sulfonamides are more effective when administered early in the course of a disease. Chronic infections, particularly with large amounts of exudate or tissue debris present, often are not responsive.

 

In severe infections, the initial dose should be administered IV to reduce the lag time between dose and effect. For drugs with a long elimination half-life, the initial dose should be double the maintenance dose.

 

Adequate drinking water should be available at all times, and urine output monitored. A course of treatment should not exceed 7 days under usual circumstances. If a favorable response is seen within 72 hr, treatment should be continued for 48 hr after remission to prevent relapse and the emergence of resistance.