Equisul-SDT

Oral trimethoprim-sulfadiazine for susceptible bacterial infections in horses; respiratory, urinary, and soft tissue infections. Combination sulfonamide-potentiated antibiotic (trimethoprim-sulfadiazine). Mechanism: sequential blockade of folate synthesis pathway — sulfadiazine inhibits dihydropteroate synthase (PABA competitive antagonist); trimethoprim inhibits dihydrofolate reductase → synergistic bactericidal effect at subtherapeutic individual concentrations. 5:1 fixed ratio of sulfonamide:trimethoprim. Key information Sulfadiazine/trimethoprim combination. Ensure adequate water intake to prevent crystalluria. First dose may need to be a loading dose. Sulfonamide — avoid in sulfa-sensitive animals. Monitor CBC with prolonged use.

Oral powder (horses): mix into grain or water. Oral tablets (small animals): Administer orally. May be given with food to improve compliance and reduce GI upset. Administer with food to reduce GI adverse effects. Administer at consistent times; complete full course. Store at room temperature; protect from light. If a dose is missed Administer as soon as you remember. If it is almost time for the next scheduled dose, skip the missed dose and resume the normal schedule. Never double up doses to make up for a missed one. Ensure adequate water intake. Complete the full course.

GI: anorexia, vomiting, diarrhea. Renal: crystalluria, urolithiasis (ensure hydration). Hematologic: anemia, thrombocytopenia, leukopenia (prolonged use — monitor CBC). KCS/dry eye in dogs (prolonged use). Hepatotoxicity (rare). Sulfonamide hypersensitivity (fever, skin rash). Folate deficiency.

For animals Ensure adequate water intake (crystalluria prevention). Reduce dose or extend interval in renal impairment. Monitor CBC periodically with prolonged use. Dogs: monitor for KCS with prolonged use. Monitor liver enzymes with prolonged use. Avoid in patients with sulfonamide hypersensitivity. Use with caution in pregnant animals. For people handling this medication Wash hands thoroughly with soap and water after handling. Avoid contact with eyes; if contact occurs, flush with water for 15 minutes and seek medical attention. Keep out of reach of children. If accidental ingestion occurs, contact Poison Control (1-800-222-1222). Potentiated sulfonamide — inform your doctor if sulfa-allergic. Wash hands thoroughly with soap and water after handling. Keep out of reach of children. Pregnant women and women of childbearing age should avoid contact.

Contact your veterinarian. Sulfonamide overdose causes crystalluria (kidney), GI signs, and blood effects.