Dogs taking prednisone for more than three months are at increased risk of long-term side effects such as Cushing's disease, diabetes, obesity, urinary tract infections, and bacterial and fungal infections. Other side effects resulting from long-term use include muscle weakness, thinning of the coat, calcium deposits, demodectic mange and other skin conditions, according to VCA Animal Hospitals.
To reduce the risk of long-term side effects, owners should take their dogs for quarterly exams by a veterinarian to re-evaluate the dog's condition and explore alternative treatments, recommends VCA Animal Hospitals. The dog should have blood and urine tests every six months and taper off of the prednisone dosage as treatment progresses.
Dogs taking prednisone for less than three months are also at risk of side effects, though they may be less severe. These include vomiting, bacterial skin infections, lethargy, panting, and increased urination, thirst and hunger, explains VCA Animal Hospitals. These short-term side effects usually lessen by decreasing the frequency or dosage of the prednisone, or by prescribing a different medication in its place.
Even on a short-term prescription of prednisone, dogs that are pre-diabetic are at risk of developing diabetes as a side effect. However, once the dog finishes the prescription, the diabetes resolves. Prednisone often improves a dog's quality of life and can be a life-saving medication. Doctors generally consider it to be safe for dogs, with its benefits greatly outweighing its risks, reports VCA Animal Hospitals.