DP replied: "Side Effects Side effects seen in dogs include polyuria, polydipsia, polyphagia, poor haircoat, GI disturbance, diarrhea, vomiting, weight gain, GI ulceration, pancreatitis, lipidemia, elevated liver enzymes, diabetes mellitus, muscle wasting, and possible behavioral changes. Polyuria, polydipsia, polyphagia may be seen in dogs even on short-term therapy. Corticosteroids can cause or worsen gastric ulcers. Precautions Chronic or inappropriate use of corticosteroids, including prednisone, can cause life threatening hormonal and metabolic changes. Adverse effects due to corticosteroid treatment usually occur with long-term administration of the drug, especially when high doses are used. Alternate day therapy with short acting preparations is preferred. Animals who have received long-term therapy should be withdrawn slowly by tapering the dosage and prolonging the interval between doses. Corticosteroids suppress immune response. Animals receiving systemic corticosteroids may be more susceptible to bacterial or viral infections. Systemic corticosteroids can mask signs of infection, such as an elevated temperature. Systemic corticosteroids are contraindicated in patients with systemic fungal infections. (The treatment of Addison's disease may be considered an exception.) Prednisone must be converted to prednisolone in the liver. Animals in hepatic failure should receive prednisolone rather than prednisone. Corticosteroids should be avoided or used very carefully in young animals both because of immune suppression and the risk of GI ulcers."