Table 58-5.

Pharmaceutical Therapy of Large Bowel Inflammation

Drug Category and Name	Dosage Recommendation	Indication
Antimicrobials
Enrofloxacin Metronidazole	5 mg/kg PO once daily (D) 10 to 15 mg/kg PO BID (D, C) to TID (D) For metronidazole benzoate increase above dose by approximately 50%	HUC Acute and chronic colitis
Antiinflammatory Drugs
Sulfasalazine	10 to 30 mg/kg PO TID for 4 to 6 weeks, max 1 g total dose (D) 5 to 12.5 mg/kg PO TID for 2 to 4 weeks (C) Administer with food; slowly decrease in 10- to 14-day steps to BID, then half the dose BID, then once daily; regularly measure tear production	Colonic IBD refractory to diet and metronidazole
Immunosuppressive Drugs
Prednisone	1 to 2mg/kg PO bid for 10 to 14 days, then slow tapering over several weeks	Colonic IBD refractory to diet and antibiotics
Azathioprine (D)	Starting dose 2 mg/kg PO once daily for 2 weeks, then 2 mg/kg every other day for 2 to 4 weeks, then 1 mg/kg PO every other day May take 2 to 4 weeks to take effect	Steroid-refractory colonic IBD
Chlorambucil (C)	Cats weighing >4 kg: 2 mg per cat PO every other day for 2 to 4 weeks then tapered to the lowest effective dose (2 mg/kg PO per cat every 3 to 4 days) Cats weighing <4 kg are started at 2 mg/kg per cat every third day	Refractory or severe feline IBD, combined with prednisolone
Cyclosporine (D)	5 mg/kg PO once daily for 10 weeks	Steroid-refractory chronic colonic IBD

C, cat; D, dog.