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PEER REVIEWED 36 CE: INFLAMMATORY BOWEL DISEASE TREATMENT IBD patients with mild to moderate clinical disease activity and normal serum albumin concentrations are first treated sequentially with dietary and antibiotic trials. If they fail to respond to either of these trials, immunosuppressive therapy is initiated. Diet A positive response to a dietary trial allows the patient's disease to be classified as FRE, a term that includes both dietary allergy and intolerance. The primary option for a dietary trial is switching to a diet that leads to antigenic modification (eg, novel protein source, protein hydrolysate). The diet must be palatable and introduced in gradually increasing amounts over 4 to 7 days. In dogs with FRE, a clinical response is usually observed within 1 to 2 weeks of changing the diet. In one study, dogs that responded to diet were younger and had higher serum albumin concentrations and predominant signs of large bowel diarrhea compared with dogs that did not respond to diet. 33 Antibiotics An antibiotic trial typically involves administration of tylosin, oxytetracycline, or metronidazole ( TABLE 2 ). A positive response suggests ARD. The patient is typically maintained on antibiotics for 28 days. If signs recur after discontinuation of therapy, long- term antibiotic therapy is instituted with tylosin. Anti-inflammatory and Immunosuppressive Therapy Patients that do not respond to a diet or antibiotic trial are usually administered prednisolone or prednisone ( TABLE 2 ). However, as the side effects of glucocorticoids are usually more marked in large- breed dogs than in small breeds, azathioprine may be combined with glucocorticoid treatment for a faster taper period in dogs weighing >30 kg. If there is poor response to immunosuppression or a relapse is seen after tapering, cyclosporine may be considered. In cats, chlorambucil with prednisolone is used if the response to glucocorticoid treatment is inadequate. Hematologic parameters should be monitored regularly if chlorambucil is used. If the patient responds, then the medication can be tapered gradually, starting with the steroid, to a q48h dosing regimen. Budesonide is a glucocorticoid medication that has been shown to be successful in the treatment of canine IBD. 53,54 However, hypothalamic–pituitary– adrenal suppression and development of steroid hepatopathy has been demonstrated in dogs. Therefore, the hepatic first-pass effect of this drug in dogs may not be as beneficial as in human beings. 54 An optimal dose of budesonide has not yet been determined. The response rate to budesonide has been shown to be similar to prednisone; however, this drug should be reserved for dogs that are known to respond to steroids but suffer severe TABLE 2 Dosages of Drugs for Management of Chronic Enteropathies DRUG CLASSIFICATION DRUG DOSAGE Antibiotic Tylosin 10 to 15 mg/kg PO q8h for 28 days 5 mg/kg PO q24h, long-term Oxytetracycline 20 mg/kg PO q8h for 28 days Metronidazole 10 mg/kg PO q12h for 28 days Anti-inflammatory and immunosuppressant Prednisolone 2 mg/kg PO q24h for 2 weeks, then tapered over 6−8 weeks Cyclosporine 5 mg/kg PO q24h for 10 weeks 5 to 10 mg/kg PO q24h Chlorambucil 2 to 6 mg/m2 PO q24h Budesonide 1 mg/m2 PO q24h Sulfasalazine 20 to 50 mg/kg PO q8h for 3 to 6 weeks