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

Surgical Admit Appointments & Day-Of Electives: A Cat Owner’s Manual

Hi, I’m Dr. Lauren! Read my introduction to learn more about me and my two adventurous cats, Pancake and Tiller. Surgery of one’s...

9 Best Cat Foods for Diarrhea in Canada in 2025: Reviews & Top Picks 

As lucky as we are to parent our fluffy family members, it isn’t a job that comes without some pretty gross cleanups, smells,...

Cats, Humans, & Mental Health: Dr. Lauren’s Thoughts on Well-Being & Reciprocity

I remember watching the news with some curiosity, and a sense of impending change. “Hold on to your socks,” someone said, “this is...

Why Do Cats Like Warm Things So Much? 6 Interesting Reasons

You may have seen your cat cuddling with things like air vents or heaters. This may pique your interest, causing you to wonder...

More related

Gabapentin for Cats: Uses, Doses & Side Effects (Vet Answer)

Many human drugs are also used in pets, and gabapentin is one such drug. This medicine is used in veterinary medicine as an...

Lead Poisoning in Cats: Our Vet Explains the Causes, Signs & Treatment

Lead poisoning in cats is an issue you definitely want to avoid for your pet, and it’s a diagnosis that no cat owner...

How to Train Your Cat to Use a Cat Door: 6 Vet-Approved Tips

Whether you’re installing a cat door in your home for the first time or have just moved somewhere that already has one, it...

What’s Your Take on Cat Strollers? Why Olga Isn’t the Ideal Candidate

Hi, I’m Christopher! Read my introduction to learn more about me and my silly Russian Blue cat, Olga. Most of the pet owners...

Keep reading

What Happens When a Cat Is in Heat? Vet-Verified Facts & FAQ

A cat’s heat cycle is an indication that she has reached sexual maturity, is fertile and can become pregnant. If this is your first time going through a heat cycle with your female cat, you may be wondering what on...

Ginger tabby young cat sitting on a wooden floor looks up, asks for food, meows

Rare Cannabinoid Company Hawaiian Choice Pet CBD Oil Review 2025: A Detailed Look

By now you’ve no doubt heard about the benefits of CBD for humans. You’ve probably also heard that this hemp product can be beneficial for dogs. But what about cats? Believe it or not, all mammals (and most other animals,...

Rare Cannabinoid CBD Pet Oil

Why Does My Cat Sit In My Chair? 5 Vet-Approved Likely Reasons & Prevention Ideas

Have you recently noticed that your furry companion has hijacked your chair? Every time you walk into a room, they are sitting in the seat of your chair or up on the back. This might be an odd behavior to...

ginger cat sitting on an armchair

Why Is My Cat Peeing Outside the Litter Box? 7 Possible Vet-Approved Reasons

Cat pee is not a pleasant odor, even when it’s safely contained in a litter box. However, when a cat starts urinating in inappropriate locations, the situation escalates. Inappropriate urination is a common reason that cats are surrendered to animal...

orange cat beside litter box

Why Do Cats Trill When They Jump? 4 Vet-Reviewed Reasons

In the wild, cats remain fairly silent. Their purrs, hisses, growls, and yowls are mainly for communication, not something they do casually as they go about their day. So, why do our domestic kitties get so vocal when they jump?...

cream-colored-maine-coon-cat-jumping-over-the-couch_Nils-Jacobi_shutterestock

Why Is My Cat Throwing Up White Foam? 8 Vet-Reviewed Reasons

Cats vomit for several reasons. As unpleasant as it sounds, the color and consistency of your cat’s vomit may give you and your veterinarian a clue as to the reasons why. What if your cat is throwing up white foam?...

cat-vomitting

7 Health Benefits of Catnip for Cats – Based on Science

Most of us cat parents know that many cats have a weakness for catnip. So, while we might want to select a catnip-filled toy, are there actually any health benefits to allowing your cat to have catnip? The good news...

cat with green eyes in catnip

Why Is My Cat So Obsessed With Water? 8 Vet-Reviewed Reasons & Tips

You might expect a cat to be obsessed with food—but water? Whether it’s drinking excessively, tipping the bowl over, splashing their paw around in it, or trying to get in the shower with you, some cats take a particular shine...

cat drinking from cat water fountain