Get

In Your Inbox

Catster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

What are the Side Effects of Prednisolone & Prednisone? Our Vet Explains

pile of white round tablets

Glucocorticoids like prednisone and prednisolone have many useful functions in veterinary medicine. In fact, they have been prescribed as a treatment for nearly every issue that you can think of. While these medications may be a helpful part of your cat’s treatment regime, you should know that they have potential side effects. In this article, we examine these possible side effects so you know what to look for if your cat is taking these medications.

divider 1 paws

What Are Prednisone and Prednisolone?

Prednisone and prednisolone are glucocorticoids, which are natural hormones made by a body’s adrenal glands. Their main function is to break down fat and sugar stores to be used for energy during times of high need (e.g., running from a predator).

In veterinary medicine, it’s not typically necessary to boost a cat’s fight-or-flight response. Instead, glucocorticoids are used for their secondary functions: fighting inflammation and suppressing the immune system. They can also be given for diseases where there is a glucocorticoid deficiency, such as hypoadrenocorticism, and as part of certain cancer treatment protocols. They are used for both short- and long-term treatment.

To be clear, in basic terms, prednisone and prednisolone are the same thing. In most mammals, prednisone is converted to prednisolone in the liver. However, cats (and animals with liver failure) can’t efficiently perform this process, so it’s more common to just prescribe prednisolone instead of prednisone so that the conversion is already done, providing them with a usable form of the glucocorticoid.

Therefore, these two products have similar actions and side effects. From this point on, we refer to prednisolone use in cats, with the understanding that if your cat were to take prednisone instead, the side effects would likely be the same.

pile of white round tablets
Image Credit: Elena Elisseeva, Shutterstock

What Are Prednisone and Prednisolone Used for in Cats?

The most common use for prednisolone in cats is as an anti-inflammatory agent. Felines with chronic asthma or other respiratory issues, inflammatory bowel disease, skin issues, joint pain, and dental disease may all benefit from prednisolone’s inflammation-fighting capabilities.

There’s also cross-over use as an immunosuppressant with these issues and auto-immune diseases, including lupus. Cats with glucocorticoid deficiency, such as those with hypoadrenocorticism or damage to the adrenal glands, will need glucocorticoid therapy to replace those missing hormones. Prednisolone is also partly used as a treatment for cancers like lymphoma, leukemia, and mast cell tumors.

It can be a helpful medication, but it’s not one to be given lightly. The use of prednisolone, especially for the long term, has been associated with various side effects.

What Are the Side Effects of Prednisone and Prednisolone in Cats?

sick grey tabby cat
Photo Credit: chie hidaka, Shutterstock

No medication is without potential side effects. Fortunately for our feline friends, they seem to suffer fewer side effects from prednisone or prednisolone administration than their canine counterparts. The side effects that are seen tend to be more prevalent in kitties taking high doses for long periods of time.

With that in mind, the most commonly seen side effects of prednisone and prednisolone in cats are as follows.

Short-Term Side Effects

  • Increased Thirst and Urination: These are scientifically called polydipsia and polyuria. Essentially, prednisolone tells the kidneys to conserve more salt, which makes the body want to consume more water to maintain a healthy balance. The more a body drinks, the more it pees.
  • Increased Appetite: Prednisolone may increase your cat’s desire for food by triggering the hunger center in the brain. Cats may be ravenous and beg for food constantly.
  • Vomiting /or Diarrhea: Glucocorticoid treatment, especially in the early stages, can cause some digestive upset.

Long-Term Side Effects

  • Weight Gain: A bigger appetite often leads to a bigger kitty. If you give in to your cat’s cravings for food, they may put on extra pounds.
  • Lethargy or Depression: You may notice that your kitty doesn’t have the spring in their step that they used to with longer courses of prednisolone.
  • Increased Risk of Infection: Prednisolone is an immunosuppressant, so using this medication for the long term could put your cat at risk for infections, mainly urinary tract and skin infections, along with decreased wound healing.
  • Increased Risk of Diabetes: Long-term and high-dose glucocorticoid administration can increase the risk of insulin resistance in the body tissues, leading to a diabetic situation.
  • Cushingoid Effects: These are signs that look like Cushing’s disease. It mainly happens with high doses given for a long period and can present with thinned hair and skin, a potbellied appearance, and recurrent ear, skin, and urinary tract infections.

If your pet is showing these signs, we suggest you speak to a vet.

If you need to speak with a vet but can't get to one, head over to PangoVet. It's an online service where you can talk to a vet online and get the advice you need for your pet — all at an affordable price!

PangoVet_Mention-in-Content for PangoVet2 save money

divider 1 paws

How to Minimize Prednisone and Prednisolone Side Effects in Cats

man petting a sick siberian cat
Image Credit: Olesya Alexandrova, Shutterstock

A veterinarian is aware of the potential for these side effects to show up in your cat, and the possibility of your kitty developing these is closely weighed with the benefits that they will receive from the medication. Vets also take care to prescribe dosing guidelines that you should tightly adhere to. Their goal is to use the smallest dose possible for the shortest amount of time in order to get your cat the greatest benefit.

Therefore, felines are usually started at a dose high enough to achieve relief from clinical signs. Once that relief is achieved, the vet will try to decrease the prednisolone dose to a lower maintenance level. This often means every-other-day administration. From there, depending on the issue that your cat needs treating, prednisolone use will be further tapered off until it can be stopped completely, or your cat will be maintained on the lowest dose possible.

If you notice any of these side effects in your cat or anything else abnormal, contact a vet. They may be able to adjust the dose or prescribe a different medication. Prednisolone isn’t the only option out there, and your cat may be better suited for a different course of treatment.

divider 1 paws

Frequently Asked Questions

How Are Prednisone and Prednisolone Administered to Cats?

Prednisolone is available as an injectable or a tablet. The vet may use the injectable form in the clinic, but at-home administration is nearly always a tablet. If you’ve never given a cat a pill, be well-prepared beforehand, as cats can be quite particular about this process.

woman giving a medicine tablet to her cat
Image Credit: New Africa, Shutterstock

What Happens If I Suddenly Stop Giving Prednisolone to My Cat?

Besides the desire to decrease the dose of prednisolone to the smallest amount necessary, the vet will have you taper the dose near the end of administration to help avoid issues. When a cat takes prednisolone, especially for the long term, their body may reduce the amount of prednisone that it normally produces. Then, if you suddenly stop giving the medication, their body no longer has enough for normal function, and your cat may become quite ill. Tapering the dose enables the body to gradually adjust its normal production to fit its needs.

divider 1 paws

Conclusion

Prednisone and prednisolone are useful medications in veterinary medicine. They can treat many health issues and make a significant difference in the way that a cat feels. However, they are not miracle drugs, and administration should be closely monitored by you and a vet. Many potential side effects may also pop up, so be sure to talk to a veterinarian any time you have questions about your cat’s prednisolone regime.


Featured Image Credit: Alexander Khoruzhenko, Shutterstock

Want content like this delivered to you?

Sign Up For Our Newsletter

News, insights, expert advice, and everything cat

* By submitting, you agree to our Terms & Conditions and Privacy & Cookies Policy.

How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Catster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.

Talk With A Vet Online

Peace of mind,
anywhere, anytime

Affordable vet advice

9 Amazing DIY Cat Carrier Plans You Can Make Today (With Pictures)

Every human cat companion needs a high-quality carrier for their buddy. Even if your cat dislikes leaving the confines of their home, there...

Black Sphynx Cat: Info, Pictures, Care & Facts

The Black Sphynx is one of several colors of the Sphynx cat. The Sphynx is best known for their hairless appearance and wrinkled...

9 Types of Cat Toys & How to Use Them (With Pictures)

Cats love to play (though they can be picky about what they’ll play with), and for good reason! Play is an integral part...

Can Cats Eat Pumpkin Puree? Vet Approved Facts & Nutrition Guide

When people think of pumpkins, they usually think of falling leaves, bonfires, chilly temperatures, and seasonal treats. However, did you know that some...

More related

Ask Dr. Paola – Incontinence, Hiding & Plant Safety (September 8, 2025)

Welcome to our “Ask Dr. Paola” series, where every Monday we bring expert advice straight from Dr. Paola Cuevas (MVZ) to help our...

When to Euthanize a Cat With Feline Leukemia: Vet-Reviewed Advice

Feline leukemia is a serious disease that can cause a wide range of signs in cats, including anemia, weight loss, and infections. Unfortunately,...

Does Lyft Allow Cats? Pet Policy & Travel Tips

There are times in life when you might need to travel with your cat. Whether you are flying on vacation or trying to...

Swimmer Syndrome in Cats: Our Vet Explains Causes, Signs & Treatments

Swimmer syndrome is a developmental abnormality that occurs in newborn kittens. The condition can be observed starting at the age of 15–20 days....

Keep reading

Why Do Cats Meow Back at You? 5 Vet-Reviewed Reasons for This Behavior

If you have a cat, you might have noticed that they sometimes meow back at you when you talk. Some cats will even meow at you when you sneeze or make a noise. The anecdotal explanation for this behavior is...

black cat

Can Cats Eat Grits? Vet-Reviewed Health Risks & Advice

Whether it’s because we’ve decided to give them a treat or because they’ve gotten into it themselves, our cats can eat quite a bit of people food. And, a lot of the time, this is okay—so long as whatever they...

Can Cats Eat Grits

Why Does My Cat Pee on Plastic Bags? 6 Vet-Reviewed Reasons & Solutions

If you’ve ever come home to find that your cat has peed on a plastic bag, you’re not alone. This odd behavior is surprisingly common in cats for a variety of reasons. The reasons could be as plain as a...

cat lying inside a plastic bag

How to Tell if My Cat Still Has Kittens Inside: 10 Vet-Reviewed Signs

If your cat is pregnant, you want the birthing process to go smoothly. As your soon-to-be mother cat prepares to give birth, she’ll be restless and vocal, groom herself excessively around her vulva, pant more, and eat less. She’ll also...

tabby mother cat feeding her kittens

7-12-Month Old Kitten: What to Expect (Vet-Verified Guide)

Most kittens get adopted before they are six months old, meaning that you get to experience the part of a kitten’s life in which they are 7 to 12 months of age. This is the stage where kittens are self-sufficient...

Australian Mist Kitten

How to Tell if Your Cat Is Happy: 16 Vet-Reviewed Signs

Some people prefer dogs to cats because dogs are considered easier to read and more demonstrative with their affection. Many cat enthusiasts will insist that if you know what you’re looking for, it’s quite easy to know if your cat...

bengal cat being stroked by man's hand and purring

How to Clean a Cat’s Butt: Vet-Approved Step-by-Step Guide

Cats are generally experts at cleaning themselves, butts included. But sometimes, your feline pal needs a little extra help in the hygiene department. Cleaning a cat’s butt is mildly unpleasant and can also be a health risk, so ensure you...

A-curled-cats-tail-close-up

Can Cats Eat Hard-Boiled Eggs? Vet-Verified Nutrition Facts & FAQ

It’s difficult not to treat your furry friend to a little piece of your meal, but there’s always some concern as to whether our cats can indulge in the same foods that we do. That concern is amplified with foods...

Can Cats Eat Hard-Boiled Eggs