This is not medical advice. Before pursuing feeding your dog a new food, supplement, or medication it’s advised to consult with your veterinarian.

Prednisone is a type of corticosteroid medication often prescribed to dogs and cats. These kind of steroid hormones are not the same kind of steroids that humans use for building muscle, even though medicines like prednisone are often referred to as a steroid. Prednisone is specifically a glucocorticoid that is similar to a hormone called cortisol that is produced by your cat’s adrenal glands. You have adrenal glands that make cortisol too! You have likely heard of cortisol being referred to as a “stress hormone”, so why do vets give corticosteroids like prednisone to cats?

Well, cortisol has a lot of important jobs in the body, including breaking down sugars, helping the body heal, and reducing swelling and inflammation. It’s these beneficial actions that your vet is trying to mimic with prescribed corticosteroids like prednisone. Other things that corticosteroids do include suppressing the immune system (at very high doses), inhibiting healing, altering mood, stimulating your pet’s appetite, increasing the amount of gastric acid made by the body, weakening the muscles, and thinning the skin.

Some of those things, like reducing inflammation and swelling sound good, but what about some of those other effects? Prednisone and similar medications are used for very specific reasons and given to cats at the lowest dose possible to have the desired effect, and for the shortest time possible. This is so any adverse side effects can be avoided as much as possible. Also, these side effects are why it is important to only be giving medications like prednisone to your cat with a vet’s supervision. This is not a medicine to be giving your cat on your own!

Why Are Corticosteroids Prescribed?

Prednisone and other corticosteroids are used to treat a lot of different ailments in cats. There is a large range of use for prednisone. On one end of the spectrum is using low doses of prednisone to treat an inflammatory condition like asthma. On the other end of the spectrum, your vet may prescribe a larger dose to suppress your cat’s immune system. Conditions that smaller doses of prednisone treat are:

  1. Asthma

  2. Other respiratory conditions

  3. Allergies

  4. Dermatitis

Conditions your vet might use a larger dose of prednisone for are:

  1. Inflammatory bowel disease

  2. Hyperactive immune system

  3. Polyarthritis

  4. Meningitis

  5. Hemolytic anemia

  6. Other immune-related conditions

What Side Effects Can Corticosteroids Cause?

Medicines given by mouth or through injection need to be processed by the body, which means they go through the liver and the kidneys. This is one reason why vets try to only prescribe the exact amount of prednisone needed to treat your cat’s health issues. There is a difference in side effects between prednisone given short term and prednisone given long term.

Short-Term Side Effects

This is a list of side effects to expect when your pet first starts their corticosteroid treatment. These side effects will vary depending on how much and how often your vet is having you give prednisone to your cat. 

1. Increased thirst and urination.

Make sure you leave out plenty of fresh water for your cat, and you may need to change their litter box more since they’ll be using it frequently.

2.  Increased hunger.

If your cat is still begging for food after their usual meal and treats, try switching to low-calorie treats. Cooked carrots and zucchini are among some of the low-calorie foods that are safe for cats. 

3. General loss of energy.

If your cat is napping a lot more than usual, consider investing in a cozy bed or blanket to help them stay comfortable. 

4. Infections.

With prednisone use, infections are more prone to developing. If your cat had an infection before starting prednisone, it could get worse. 

5. Vomiting or nausea.

Signs of nausea in cats include less of an appetite, licking, restlessness and drooling, excessive chewing, lots of meowing. Nausea can make your cat uncomfortable, which makes it hard for them to settle. 

6. Diabetes.

If your cat was pre-diabetic, prednisone can cause diabetes to fully develop. Once your cat is off the prednisone, the diabetes will heal. 

Long-Term Side Effects

Despite the common veterinary practice of only using the lowest possible dose for the least amount of time, there are some instances when long-term use of prednisone is needed. In these cases, prednisone is used to treat a chronic illness or condition. Here are some of the side effects that long-term use of prednisone can cause.

1. Urinary tract infection

Because prednisone reduces inflammation, it’s possible for your cat to develop a UTI and not feel it.

2. Skin Issues

Your cat’s skin could develop blackheads (which are small blemishes) or start to become thin. 

3. Fur issues

Your cat’s coat of fur can lose its shine, or start to thin out. Gentle grooming with a soft brush and a fish oil supplement might help. Cannabinoids (CBD) from hemp may also help support healthy skin.

4. Wounds healing more slowly

Make sure you keep any wounds clean with a vet-approved disinfectant like saline solution. 

5. Obesity

Ask your vet about a good diet food to give your cat, look into low-calorie treats like cooked vegetables, and try to keep your cat active with interactive toys and games. 

6. Muscle weakness

This is caused by a breakdown of protein in your cat’s muscles. Support your cat’s mobility with a set of stairs up to your bed, or his favorite window. 

7. Calcinosis Cutis

This is when calcium builds up under the skin and causes hard spots on the skin called plaques. 

8. Bacterial infections

These are due to the suppression of your cat’s immune system. 

9. Fungal Infections

This is also due to the effects long-term prednisone use can have on the immune system. CBD promotes the body’s innate resistance to pathogens. Make sure you wear gloves and wash your hands often if it’s a contagious fungus, like ringworm.

10. Diabetes mellitus

Unfortunately, prednisone use can lead to your cat developing diabetes. If your vet has your cat on a long-term dose of prednisone, and you aren’t sure it’s right for your cat, feel free to get a second or third opinion about your cat’s course of treatment. However, if prednisone is the life-saving option, then diabetes can be treated as well.

Corticosteroids and Cushing’s Disease

One unfortunate result of long-term steroid use is the potential for developing Cushing’s disease. This is called iatrogenic, or medication-caused, Cushing’s disease. Sometimes Cushing’s disease is unavoidable when a cat must be on a long-term dose of prednisone. Vets have several strategies for avoiding this situation, however, including tapering your cat off the steroids and using different drugs in combination. Symptoms of Cushing’s disease include an increase of thirst and hunger, a pot-belly, thinning skin, infections of the skin and ears, and urinary tract infections.

Cats and Corticosteroids

While long-term use of prednisone can certainly be problematic, these corticosteroid medicines like Prednisone, are powerful and helpful drugs. Veterinary science has come a long way in the last hundred years. Pet owners can be very grateful for the advances in veterinary medicine that have given us so many tools to be able to help our pets. 

Cat owners also have so many other ways to help their cats. Ask your vet about acupuncture, dietary changes, herbal and nutritional supplements, CBD, and other strategies for lowering your cat’s inflammation in addition to prednisone or a corticosteroid. Creating a holistic plan of action that works together is the best option for your cat’s health, and your vet may have a lot of good suggestions.