Quick answer
Prednisolone for cats is a prescription steroid that calms inflammation and an overactive immune system. Vets use it for allergies, asthma, inflammatory bowel disease and some cancers. Cats are usually given prednisolone rather than prednisone, because their liver converts prednisone poorly. Common effects are more thirst, peeing and hunger. Your vet will set the dose for your cat, and it shouldn't be stopped suddenly.
What is prednisolone used for in cats?
Prednisolone is a corticosteroid, a man-made version of the cortisol hormone the body makes on its own. It’s a different kind of steroid from the muscle-building ones people misuse. Vets prescribe prednisolone for cats often because it works well, is affordable and comes in easy-to-give forms. Its main job is to calm inflammation and, at higher doses, to dampen an immune system that’s attacking the body.
| Condition | Why it helps |
|---|---|
| Allergies and itchy skin | Reduces itching, redness and overgrooming |
| Feline asthma | Calms swelling in the airways so breathing is easier |
| Inflammatory bowel disease | Settles gut inflammation that causes vomiting and diarrhea |
| Immune diseases | Stops the immune system attacking red blood cells, skin or other tissue |
| Some cancers, such as lymphoma | Part of chemotherapy or comfort care |
| Mouth inflammation (stomatitis) | Eases pain and swelling in some cats |
Because it treats so many conditions, your vet will explain what it’s meant to do for your cat and how long the course will be.
Why do vets prescribe prednisolone instead of prednisone?
Prednisone and prednisolone are closely related. Prednisone only works after the liver converts it into prednisolone. Cats don’t do that conversion well, so less of the medicine reaches the body in its active form.
For that reason, vets usually prescribe prednisolone for cats. If you’re given prednisone for your cat, or a pharmacy offers to swap one for the other, check with your vet first.
How is prednisolone given to cats?
Prednisolone is usually given by mouth. Your vet will set the dose for your cat and tell you how often to give it. Doses are often higher at the start and then slowly lowered.
- Tablets. Small tablets can be hidden in a treat or pill pocket, or given with a pill popper
- Liquid. Compounding pharmacies can make flavored liquids, which some cats accept more easily
- Injections. Your vet may use a long-acting steroid injection instead when giving tablets isn’t possible. That’s a different product with its own risks, so ask what’s being given
Giving each dose with food can help prevent an upset stomach. Keep a simple chart of each dose given, especially while the dose is being lowered, so nobody in the house skips or repeats one. If your cat spits out or won’t take a dose, call your vet rather than doubling up next time.
Why shouldn’t prednisolone be stopped suddenly?
When your cat takes prednisolone for more than a short time, their body makes less of its own cortisol. Stopping suddenly can leave them without enough, which can cause weakness, vomiting and collapse. Your vet will taper the dose down over days or weeks before stopping.
What are the side effects of prednisolone for cats?
Cats tend to handle this medicine better than dogs and people, and short courses rarely cause problems. Effects are more likely at high doses and with long-term use.
| Effect | When it’s likely | What to do |
|---|---|---|
| More thirst and peeing | Common, even on short courses | Keep water available. Mention it at your next visit |
| Bigger appetite, weight gain | Common | Stick to normal portions |
| Mild behavior changes | Sometimes | Tell your vet if it worries you |
| Urinary tract infections | Long-term use | Your vet may test urine even without signs |
| Diabetes | Long-term or high doses | Call your vet about thirst plus weight loss |
| Thin skin, poor coat, muscle loss | Long-term use | Discuss at rechecks |
| Black stool or vomit with blood | Rare | Call your vet now |
Prednisolone can hide the usual signs of infection. VCA notes that urinary infections occur in up to 30% of cats on long-term corticosteroid treatment, often without obvious signs, so regular urine checks are common.
In cats that are already at risk, prednisolone can trigger diabetes. The early signs are a cat drinking a lot of water and losing weight despite eating well. In many cats the diabetes goes away once the dose is reduced or the medicine is stopped.
Which cats shouldn’t take prednisolone?
Tell your vet about every health problem and medicine before your cat starts prednisolone. It may need extra care, or a different treatment, in cats with:
- Diabetes, or a high risk of it, such as overweight cats
- Heart disease. Prednisolone can increase fluid in the bloodstream and trigger heart failure in some cats
- Infections, including fungal infections and some viral ones, because it weakens the immune response
- Eye ulcers, which it can make worse
- Stomach ulcers or kidney disease
- Pregnancy
- Upcoming allergy testing, since it can affect the results
Never give prednisolone together with an anti-inflammatory pain medicine (NSAID) unless your vet has specifically said to. The combination raises the risk of serious stomach ulcers. Pain relievers from your own medicine cabinet are riskier still. Ibuprofen and aspirin are NSAIDs themselves, so pairing them with prednisolone invites ulcers, and acetaminophen (paracetamol) is toxic to cats even without a steroid in the mix. Never give any of the three to your cat.
When should I call the vet about prednisolone?
Most cats on prednisolone need regular rechecks, often with bloodwork and a urine test, so your vet can spot problems early and lower the dose as soon as it’s safe.
Call during office hours if your cat is drinking far more than usual and losing weight, has repeated vomiting or diarrhea, or the condition being treated isn’t improving. For after-hours help, see our cat emergency guide.
For other medicines vets often prescribe, including gabapentin, browse our cat medications guides.
Frequently asked questions
Why can't cats take prednisone?
Prednisone has to be converted into prednisolone by the liver before it works, and cats do this poorly. Giving prednisolone directly works more reliably, so it's what vets usually prescribe for cats.
Does prednisolone make cats hungry?
Yes. A bigger appetite is one of the most common effects. Stick to your cat's normal portions unless your vet says otherwise, because long-term weight gain adds to the risk of diabetes.
Can I stop prednisolone if my cat seems better?
No. After more than a short course, the body needs time to restart its own steroid production. Your vet will lower the dose gradually before stopping it.
Sources
- VCA Animal Hospitals: Prednisolone / Prednisone
- VCA Animal Hospitals: Steroid Treatment, Long-Term Effects in Cats
- Merck Veterinary Manual: Corticosteroids
- Plumb's Veterinary Drug Handbook: Prednisolone
Written by the CatsMed Team from the sources above. This guide isn’t reviewed by a veterinarian and isn’t a substitute for one. See how we research.
