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Why Is My Cat’s Butt Red? 9 Common Reasons

Written by: Gregory Iacono

Last Updated on January 17, 2024 by Catster Editorial Team

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Why Is My Cat’s Butt Red? 9 Common Reasons

Being a cat parent is usually a breeze because cats are so independent. Occasionally, however, your feline friend might experience an illness or condition that demands your attention as well as the attention of your veterinarian. One of those times is when, for some reason, your cat’s butt turns a deep red color. What can cause a cat’s butt to turn red like that, and what needs to be done about it?

If you’ve noticed that your cat’s butt has suddenly turned a deep, blood-red color and you’re concerned for their health, the information below will be beneficial. We have the nine common reasons that can make your cat’s butt turn red.

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The 9 Common Reasons Why Your Cat’s Butt Is Red

1. Your Cat Has Gastrointestinal Disease

How Common?: Very (The most common cause of red butt)
Treatable?: Yes
Painful?: Sometimes

Gastrointestinal disease is what veterinarians call an “umbrella term” because it covers a variety of possible health problems. For example, gastrointestinal disease in cats can be caused by a poor diet or something foul your cat ate. It can also be caused by constipation or when your cat’s stool is too soft and filled with fluid.

The treatment for gastrointestinal disease depends on the condition’s cause and your cat’s age. Whatever the reason, gastrointestinal disease can make your cat’s butt very red due to extreme inflammation.

2. Your Cat Has Impacted Anal Glands

How Common?: Very
Treatable?: Yes
Painful?: Sometimes

Anal glands are specialized glands near your cat’s anus that lubricate it when they poop and contain the scent cats use to mark their territories. When the anal glands become impacted, anal sac disease is often the result, which will cause your cat’s anus to become swollen and red.

If the glands aren’t expressed, the impact can lead to an abscess, which can be extremely painful. That’s why it’s recommended that your veterinarian express your cat’s anal glands regularly.

3. Your Cat Has Allergies

How Common?: Moderately
Treatable?: Yes
Painful?: Sometimes

Cats can sometimes have allergies to food, cleaning products, and other items. If they come in contact with an allergen, their butt will often swell and become red and inflamed. A food allergen would likely cause diarrhea or constipation, while allergens from other causes would have to touch their butt to cause it to swell and become red.

Cleaning products are the typical culprits. Treating allergies is sometimes tricky because you first must determine what is causing the allergic reaction. Once the allergen is determined, the treatment is straightforward and usually 100% successful. You simply need to prevent your cat from eating or being exposed to the allergen in the future.

4. Parasites Have Infected Your Cat’s Colon

How Common?: Moderately
Treatable?: Yes
Painful?: Sometimes

If your cat has parasites, you will notice its poor little butt is swollen and red. That’s because parasites aren’t broken down in their colon. Because of this, the eggs and worms the parasites create end up passing through to your cat’s anus, where the nasty little critters cause it to become inflamed and irritated.

Sometimes, you can even see worms wriggling around near their anus. The treatment for parasites usually consists of one or two rounds of antiparasitic drugs.

5. There’s a Foreign Object in Your Cat’s Rectum

How Common?: Low
Treatable?: Yes
Painful?: Yes

Occasionally, your curious feline might swallow something it shouldn’t, like a bone, pebble, or another foreign object. If the material manages to get down your cat’s throat and into its GI tract, it will usually make its way to its anus, where, frequently, it will cause intense inflammation, redness, and pain as your kitty tries to push it out. If the object has a jagged edge, it could also tear your cat’s anus and cause an anal fissure or perianal fistula, which can be extremely painful. Treatment depends on the object and any problems that it might have caused.

6. Your Cat Has an Inflammatory Infection

How Common?: Moderately
Treatable?: Yes
Painful?: Yes

A red, swollen cat butt can be caused by an inflammatory infection which, like gastrointestinal disease, can have several causes. Those causes include a fungal, viral, or bacterial infection that’s either local (a single organ) or systemic (your cat’s entire body). Local infections are usually caused by bacteria that invade your cat’s anal area.

If they’ve recently had diarrhea or constipation, and their butt is inflamed, bacteria can enter and worsen the problem. Sometimes it’s caused by your cat’s own poop, which contains bacteria. The treatment depends on the cause but typically involves antibiotics or anti-viral medications.

7. Your Cat Has Colitis

How Common?: Very
Treatable?: Yes
Painful?: Sometimes

Colitis is another umbrella term for anything that causes your cat’s colon to become inflamed. The Latin suffix “itis” means inflammation. Thus, colitis means inflammation of the colon. Colitis can be caused by several things, many of which are listed above.

The two types of colitis are acute (which happens suddenly) and chronic (which keeps recurring). Either type of colitis is painful, but chronic colitis can be life-threatening for your cat and must be treated by a veterinarian. The treatment will depend on the cause of the colitis.

a siamese cat getting examined by a vet at the clinic
Image Credit: Sergey Nivens, Shutterstock

8. Your Cat Has Anal Tumors

How Common?: Low
Treatable?: Sometimes
Painful?: Yes

Some anal tumors are benign, and some are malignant, but all can cause swelling and redness on your cat’s butt. That’s because an anal tumor will get in the way when your kitty is trying to poop, causing irritation and pain. The good news is that anal tumors caused by cancer are very rare in cats and are usually benign.

Typically, the treatment involves surgically removing the tumor and testing it for malignancy. Cancer treatments are usually the next course of action if it’s malignant. If it’s benign, your cat will only need some time to heal from the surgery.

9. Your Cat Is Suffering From a Rectal Prolapse

How Common?: Low
Treatable?: Yes (Usually emergency treatment.)
Painful?: Very

This last health problem that can cause your cat’s butt to be red is also the worst. A rectal prolapse is when the rectal tissue inside your cat’s anus has protruded out of its anus. As you might imagine, this will cause their butt to be extremely red and bloody.

Rectal prolapse is often caused by a primary problem that causes your kitty to strain mightily when pooping, which results in the tissue exiting the anus. Rectal prolapse is considered a medical emergency that a veterinarian should treat immediately.



The 4 Ways You Can Help Your Cat

Depending on the cause of your cat’s red butt, you can do a few things yourself at home to relieve them. However, several causes of a red, swollen butt will need veterinary intervention to prevent your cat from developing a more severe problem.

1. Change Your Cat’s Diet

If your cat’s butt is red because they have an allergy to the food or treats, changing its diet is the best way to prevent the problem.

tabby cat eating cat food out of bowl inside
Image Credit: Africa Studio, Shutterstock

2. Express Their Anal Glands Regularly

As we mentioned earlier, impacted (blocked) anal glands can cause your cat’s butt to become red and swollen. If that’s the case with your cat, expressing their anal glands (or having your vet do it) will be necessary. You should have your cat’s anal glands expressed every 6 to 8 weeks to prevent the problem.

3. Direct Treatment to the Affected Area

Even if you know what’s causing your cat’s butt to be red and are having it treated, the swelling that causes red butt can be painful. To help your cat deal with the pain, you can apply several ointments, creams, and other solutions directly to your cat’s red booty.

They include:
  • Neosporin
  • Baby wipes
  • Vaseline
  • Cold compresses
  • Any human baby ointment made to treat an inflamed butt. It should not contain zinc since it is toxic for cats.
veterinarian doctor holds cat
Image Credit: H_Ko, Shutterstock

4. Visit Your Veterinarian

If your kitty’s butt is always red, they seem to be in pain, or you can’t figure out what’s wrong on your own, a trip to your family vet is highly recommended. Most problems that cause your cat’s butt to turn red and swell must be treated with medication, and some will need surgery. Whatever the case, a licensed vet is the best person to tell you what’s happening and ensure your cat gets the correct treatment.

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Final Thoughts

As we’ve seen, several conditions, situations, and health problems can cause your cat’s butt to turn red. Thankfully, most are treatable, and your cat will recover and be fine. Some, however, demand attention from a vet so your cat can be treated and cured. Whatever the cause, if your cat’s butt is red and appears to be painful, get them the help they need as soon as you can.

Featured Image Credit: YULIYA Shustik, Shutterstock

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