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.

Megacolon in Cats: Signs, Causes, Treatment & Prevention (Vet Answer)

Share

maine-coon-cat-using-the-litter-box

You’re likely quite familiar with your cat’s litter box habits. After all, you need to regularly scoop and clean the box, so you can note how much there is and how often everything is moving through. For certain kitties, the latter can be a bit of an issue due to frequent or repeated constipation. While there are many causes of constipation in felines, a major one that can lead to the more serious version of constipation, called obstipation, is megacolon.

Here, we discuss the ins and outs of megacolon in cats so you’ll know what signs to look for, what can cause it, and how it can be treated.

divider 1 paws

What Is Megacolon in Cats?

The colon makes up most of the large intestine. It serves a couple of purposes: to absorb water from the fecal material and to store that feces until the body’s ready to get rid of it. The walls of the colon are made of muscles that contract to move feces through the rectum and out the anus. It’s important to note that the muscles of the colonic walls are controlled by nerves that come from the spinal cord.

If a cat has a megacolon, something has disrupted the normal movement of the colon, causing feces to build up, stretch the muscular walls, and make the diameter of the colon larger. Overly stretched muscles don’t work as they should, which further increases the accumulation of feces, leading to even more problems.

What Are the Signs of Megacolon in Cats?

The first signs of megacolon often coincide with those of constipation and include straining to defecate and small amounts of feces or none at all. If you have more than one kitty residing in your household, it can be hard to notice this sign at first, as there will likely still be feces in the litter box from your other cat, but you may catch the affected kitty frequently visiting the litter box and not producing anything.

After a day or two of constipation, a cat with a megacolon will likely stop eating and become lethargic. They won’t feel well and may even show abdominal discomfort, such as not wanting you to touch their stomach or frequently moving around or shifting when lying down. Some cats may also start vomiting.

As this goes on, cats can become dehydrated or even start to lose weight. A vet will likely be able to feel the hard feces in the abdomen.

Is your cat presenting any of these signs? We suggest you speak with a vet online.

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!

Preventative wellness PGV mention keep cat healthy Preventative wellness PGV mention keep cat healthy mobile

divider cat faces 2 oct 2024

What Can Cause Megacolon in Cats?

The causes of megacolon in cats can be divided into three main categories.

1. Nerve Issues

Since the nerves controlling the movement of the colon come off of the spinal cord, a spinal injury in that area can cause megacolon. A herniated disc or spinal fracture due to trauma, or disruption from an abscess or tumor can disrupt the nerves that head to the colon, making those muscles go flaccid and enabling them to stretch and expand as the fecal material starts to build up.

Manx cat owners should know that their cat’s adorable little nubbin of a tail can come at a cost. Some individuals of this breed have what’s aptly called Manx syndrome, in which the genetics that leads to their tail-lessness also causes deformities at the end of the spine, disrupting the nerves to the colon and potentially, the bladder and hindlegs.1


2. Muscular Issues

Muscles don’t work well when they’re overly stretched, so anything that blocks the movement of feces out of the colon can lead to stretching and expansion of the muscles and the diameter of the colon. Nerve problems aside, masses, foreign objects, or hairballs can all block the passage of feces, thus enabling a build-up and muscle stretching. Constant constipation due to diet, hairballs, or something else going on with your kitty can do the same thing.

As part of this, cats that experience pelvic trauma and fractures may end up with a severely narrowed pelvic canal and have difficulty passing feces. This can also result in recurrent constipation and megacolon.


3. Idiopathic Issues

Unfortunately, many cases of megacolon happen for unknown reasons. We simply don’t know the exact cause of the disruption. Idiopathic megacolon happens more commonly in older kitties but can occur at any age.

Veteterinarian explaining to woman cat medical condition
Image Credit: Nestor Rizhniak, Shutterstock

How Do I Care for a Cat With Megacolon?

Noticing constipation in the early stages is the best way that you can help your kitty. This means paying attention to their litterbox use and monitoring them for any signs of straining or otherwise abnormal defecation. If you notice a problem, see your vet immediately, as waiting could result in your cat developing a megacolon.

Your vet will start by looking over your cat and palpating their abdomen to check for hard fecal balls. They may also use ultrasound or X-rays to determine the extent of the problem and perform blood work or other diagnostics to rule out potential causes.

From there, it’s all about getting the feces out of your cat. This often involves sedation or even general anesthesia, as it can be painful. Enemas and manual evacuation techniques will be used to remove as many poop pieces as possible. Your cat will also likely be given fluids to treat dehydration.

Once the feces are removed, the underlying issues should be treated, if possible. Problems with the spinal cord may require medication or surgery; obstructions from masses, foreign objects, or strictures should be removed; and diet may need to be addressed. If the cause is unknown, most vets will attempt medical management, consisting of medication to improve colonic motility and transit time. A low-residue diet may also be recommended, which will help the colon without adding too much fiber that will bulk up bowel movements.

For most cats, medical management may be all that’s necessary to get them through the next few months or even years with normal bowel movements. However, some cats will relapse to the point that surgery may be necessary. In these cases, a colectomy will be performed. Most or all of the colon will be removed, since it’s essentially nonfunctional. Fortunately, after a few months of soft stools, most cats return to fairly normal bowel movements and only rarely experience fecal incontinence following a colectomy.

divider 3 paws

Frequently Asked Questions

How Long Can a Cat Live With a Megacolon?

Getting a cat treated for megacolon as soon as possible is always the best route, but some people might still wonder how long a cat can live without treatment. There’s not a definite answer for this, as it will vary from case to case, depending on the cause of the megacolon, the cat’s age, and health status prior.

Are Cats With Megacolon in Pain?

As fecal material starts to build up in the colon, it can become painful and uncomfortable, especially when there is pressure on the abdomen, such as when they lie down or when it is touched.

How Do You Prevent Megacolon in Cats?

Prevention is always the best medicine, so treating your cat at the first signs of constipation can help prevent megacolon from forming. Getting prompt treatment for any injury to the spine or pelvis is also crucial. Be sure to feed your cat a high-quality, highly digestible food, treat hairballs, and prevent them from eating foreign objects.

divider single cat paw oct 2024

Conclusion

Megacolon in cats forms if there is a disruption to the innervation of the colonic muscles or if an obstruction prevents feces from moving through. The result is a stretching and expansion of the walls of the colon that encourages further fecal accumulation that can build up to dangerous levels. Getting quick treatment at the first signs of constipation or other issues affecting your kitty is your best bet to prevent megacolon. Otherwise, it can be managed medically or require surgery to treat.


Featured Image Credit: Nils Jacobi, 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.


Catster's Digital Magazine is Back!

Vet-approved health & behavior advice

Real cat stories & community features

Chatting About the Rainbow Bridge, Euthanasia, and Laughter During Grief | Chatty Cattys, Episode 24

If you’ve ever felt the loss of a beloved cat, or are dreading the day when your pet crosses the rainbow bridge, you’ll...

The Simple Reasons Cats Refuse to Let Anyone Use the Bathroom Alone

Cats have an extraordinary talent for making themselves present in the most inconvenient places, and the bathroom ranks near the top of the...

A Paw-sitive Milestone: Canada Officially Becomes a Declaw-Free Nation

Canada has officially become a declaw-free nation. On May 25, 2026, a new regulation was filed in Ontario under the Provincial Animal Welfare...

The Surprisingly Simple Ways to Help a Cat With Hairballs

Cats spend an astonishing amount of time grooming. It is part hygiene routine, part comfort ritual, and part instinct that traces back generations....

More related

How Big Should A Litter Box Be? A Vet-Approved Guide

A litter box can seem trivial when preparing for your new cat to come home. However, your cat will use the box multiple...

We Talk to Mari Lowery About Her Marvelously Creepy Cat Art

The other day, I came across a small image of some cats looking like they were plucked from a Victorian-era horror story. Reading...

12 Reasons to Love Cats: Interesting Facts You Need to Know

Cats are one of the most popular pets in the US, and about 46.5 million US households live with at least one pet...

Most Popular Cat Names That Start with Z: Popular Male & Female Ideas

With so many options to name your cat, it helps to narrow down your list. Instead of starting at the beginning of the...

Keep reading

The Real Reasons Kittens Suckle! Warning: High Level of Cuteness Follows

If you’ve welcomed a new kitten into your home, you already know they come with a whole toolbox of adorable quirks. But there’s one behavior many pet parents don’t expect: suckling. Whether it’s a blanket, a finger, or their own...

sphynx kitten, webbed feet, sucking a blanket

Do Cats Really Need Baths? Most Owners Get This Wrong

You’ve likely been scrolling through social media and seen a video of someone giving their cat a luxurious bath, complete with special shampoos and a blow-dry. You look at your own cat, sprawled on the couch, and wonder: Am I...

cat on top of bathtub

9 Best Cat Foods for Diarrhea in 2026: Reviews & Top Picks

When your cat has diarrhea, it affects the entire household. There can be additional messes to clean up and unpleasant odors to contend with. Generally, diarrhea is a short-lived experience and things will go back to normal in a short...

cat eating kibbles from red bowl

Why Do Cats Blep? 11 Vet-Veified Reasons for This Behavior

Of all the adorable habits that our cats have, blepping has got to be the cutest one out there. A blepping cat has their tongue poking out of their mouths, and it’s an adorable look! There are several reasons cats...

silly photo of a cat sticking its tongue out

Has Your Cat Food Gone Bad? 8 Vet Reviewed Signs to Look For

Cat food manufacturers follow strict guidelines to produce safe products, but after they leave the factory, they can become damaged or improperly handled during shipping. The last thing you want is to feed your cat spoiled food, but you don’t...

owner feeding his cat

What If Your Cat Isn’t a Lap Cat? 6 Vet-Approved Reasons They May Not Want to Sit With You

Cats are just so unique! Some cats are super energetic, while others are quite calm. Many cats are standoffish, but just as many are cuddly. So, why are some cats not lap cats? This can be disappointing for some owners....

A cat near his human on the couch and computer.

Siberian Cat Grooming: 4 Vet-Approved Tips & Tricks

Siberian cats have long, thick coats, and it’s necessary to maintain their coat as part of keeping your cat healthy and happy. Coat problems, like tangles, mats, and oil buildup, can all lead to discomfort, pain, and infection, so it’s...

siberian cat in wood

Are Baby Wipes Safe to Use on Cats? Vet-Reviewed Facts & FAQ

For the most part, cats are rather self-reliant creatures. They do a majority of their bathing and grooming and only occasional input from you is necessary. But there are times when felines need a little additional help to stay entirely...

Catster_Are Baby Wipes Safe for Cats

Love Cats? So Do We! Join the Catster Community

Stay informed with expert pet care insights delivered straight to your inbox! Discover professional guidance on animal behavior, feeding tips, trusted product picks, and much more.




Sign up for the Catster Email Newsletter

Stay informed with expert pet care insights delivered straight to your inbox! Discover professional guidance on animal behavior, feeding tips, trusted product picks, and much more.