From dosage to side effects, here’s what you need to know about this steroid drug if your vet prescribes it for your pup.
woman giving her dog prednisone
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So your veterinarian has prescribed prednisone for your dog. What does this mean? Prednisone is a steroid that's used in veterinary medicine to treat a variety of conditions. Before starting this medication, it's helpful to learn about potential prednisone side effects in dogs so you'll know what to expect.

What Is Prednisone Used for in Dogs?

Prednisone is a corticosteroid, or steroid hormone drug that falls under a class called glucocorticoids. Glucocorticoids occur naturally in the bodies of nearly all animals and play an essential role in regulating metabolism, immune system function, and inflammation.

Prednisone is a synthetic glucocorticoid used to treat many different conditions in many species of animals. It's especially valued for its ability to reduce inflammation and suppress an overactive immune system.

Prednisone is sometimes used interchangeably with a similar drug called prednisolone. Prednisone is converted into prednisolone in the liver. Because of this, veterinarians sometimes prescribe prednisolone over prednisone to reduce hepatic stress in dogs with liver disease.

In veterinary medicine, prednisone is often prescribed to treat the following conditions:

What Are Potential Prednisone Side Effects in Dogs?

If you've ever taken a steroid drug, then you probably experienced some undesirable side effects. Most people report extreme thirst and hunger as well as mood changes and trouble sleeping. Prednisone side effects vary from dog-to-dog and dose-to-dose, but they tend to be similar to side effects in people. 

Most dogs on prednisone will have increased thirst and urination along with a voracious appetite that can lead to weight gain. Restlessness and panting may also occur. These signs can gradually improve as the dog adjusts to the medication and should cease after the drug is stopped.

It's important to provide fresh water to dogs on prednisone, but avoid letting them drink excessive amounts at one time because it may cause regurgitation or vomiting. More drinking equals extra pee, so make sure your dog gets additional opportunities to go outside and relieve herself. Your dog will probably be seriously hungry and begging for food, but resist the urge to feed extra food as it may cause weight gain. Consider feeding smaller, more frequent meals or offering your pup some low-calorie treats throughout the day.

Long-term use or high doses may lead to more serious issues. Prednisone can impact the gastrointestinal tract, causing vomiting, diarrhea, and GI ulceration or bleeding. Dogs may develop a pot-bellied appearance as well as poor haircoat or loss of hair, all signs of Cushing's syndrome. Over time, prednisone may cause elevation of liver enzymes that leads to liver dysfunction. Contact your veterinarian right away if you notice significant side effects, Your vet may adjust the dose or switch to another medication.

Common Prednisone Dosage for Dogs

In addition to treating a variety of conditions, prednisone has a very wide dosage range. The appropriate dose depends on the weight of the dog and the specific condition being treated. In general, vets try to use the lowest effective dose for the shortest time possible in order to avoid complications and side effects.

Your veterinarian will determine the appropriate dose for your dog and provide instructions for proper administration. Prednisone is usually given to a dog orally in the form of a pill, but liquid forms are available for smaller dogs or very low doses. Dogs are often started on moderate to high doses that are gradually tapered down until they can be stopped. Some conditions can be treated with a short course of prednisone while others require long-term treatment.

Your veterinarian may recommend lab testing to monitor the effects of prednisone on your dog's body, especially with long-term treatment. This will allow the vet to see small changes and adjust the dose before complications occur.

It's important to follow your vet's recommendations regarding prednisone dose and administration. Don't stop this drug suddenly; it may cause withdrawal symptoms and health complications. This is because prednisone causes the adrenal glands to produce less cortisol. Without the prednisone, the dog's body will not have enough steroid hormones to regulate essential bodily functions. By tapering the dose down, the adrenal glands are able to gradually adjust cortisol production. 

Can Dogs Overdose on Prednisone?

Because prednisone has such a wide range of safe doses, an overdose is unlikely to cause lasting harmful effects in dogs. Dogs that ingest high quantities of prednisone typically experience gastrointestinal distress that revolves as the drug leaves the body. It is possible for high doses of prednisone to cause serious GI ulcers and bleeding.

You don't need to panic if your dog accidentally got too much prednisone, but it is important to contact a veterinarian for advice right away. Try your local vet or animal emergency center, or call a pet poison control service like ASPCA Animal Poison Control or Pet Poison Helpline. The vet may tell you to induce vomiting if an extreme amount was ingested. In addition, follow-up supportive care may be needed to manage symptoms.

Prednisone Drug Interactions

Certain drugs should not be taken in conjunction with prednisone or prednisolone. Other drugs should be used with caution. Be sure to tell your vet about all of your pet's recent medications and supplements. Prednisone has many potential drug interactions, but the most common ones are as follows:

  • Nonsteroidal anti-inflammatories (carprofen, aspirin) 
  • Other steroid medications
  • Digoxin
  • Diuretics
  • Insulin
  • Ketoconazole
  • Mitotane (Lysodren)
  • Phenobarbital