Constipation in Cats: Causes, Symptoms, and Relief Options

If you know your cat’s normal routine when it comes to pooping, you might start to worry if they haven’t passed feces for a couple of days. But if your cat goes outside, how would you know if your cat hasn’t pooped for a while? Cat constipation is much easier to treat when it’s spotted early, so in this article, we’ll cover the causes and signs of constipation in cats and what you can do safely to help your cat feel more comfortable.

Constipation in Cats At a Glance

• Cats should poop at least every 24-36 hours.
• If your cat regularly poops less often, increasing their water intake might help.
• Causes of cat constipation include dehydration, a gut blockage, hairballs, and megacolon.
• If your cat is straining, this could be a sign of more severe constipation or a blocked bladder, which requires emergency veterinary treatment.

What Is Constipation in Cats?

• Constipation is passing feces less frequently or having difficulty passing feces.
• If your cat is constipated, you might notice them straining, vocalizing, and spending lots of time in their litter box.
•  Any stools they pass may be firm, dry, and smaller than normal.

Common Causes of Constipation in Cats

1. Dehydration

Dehydration is the most common cause of constipation in cats, as it causes the stools to dry out in the large intestine, making them harder to pass. Cats tend not to drink a lot of water, so they can easily become dehydrated, particularly if they eat just dry food.

2. Low-Fiber Intake

Fiber is essential for adding bulk to the stools, drawing water in, and helping the stools pass more easily through the gut.

3. Hairballs

When your cat grooms themselves, it’s common for them to swallow hair. In small amounts, this isn’t a problem, but furballs or large quantities of hair can sometimes get lodged in the gut, causing a blockage.

4. Lack of Exercise

Obesity and a sedentary lifestyle are risk factors for constipation in cats, as the gut slows down, too. For this reason, indoor cats are particularly at risk of constipation.

5. Pain or Litter Box Avoidance

If your cat can’t position to poop without feeling pain, or if they are reluctant to use the litter box because it’s dirty or they’re being bullied by another cat, they will hold their poop. This causes the stool to dry out as it sits in the intestine, causing a blockage that worsens as more poop builds up.

6. Medications

Certain medications, like diuretics, iron, and codeine, can cause dehydration or reduce gut movement, making constipation more likely.

7. Underlying Health Conditions

Some medical conditions, including mega-colon, tail-pull injuries, and neurological conditions, can cause constipation.

Signs and Symptoms of Constipation in Cats

Straining or vocalizing in the litter box

• Hard, dry, or small stools
• Restless behavior and frequent trips to the litter box
• Lethargy
• Loss of appetite
• Vomiting
• Bloated or firm abdomen
• Licking or biting at the rear end

Some of these symptoms could also indicate a blocked bladder, which is a life-threatening emergency and can appear very similar. If your cat is straining and not passing any urine or feces, take them to the vet immediately.

When to See the Vet

If you notice any of the following signs, your cat needs to be examined by the vet:

• Your cat hasn’t pooped in more than 48 hours and seems unwell, or hasn’t pooped in 3 days if they’re acting well otherwise.
• Repeated straining with no urine or feces passed.
• Vocalizing
• Bloated or firm abdomen, or signs of abdominal pain (e.g., unusual aggression when touched)
• Blood in the stool.
• Loss of appetite
• Withdrawing or hiding.

If your cat is straining to pass feces but not passing any stools, they must see a vet immediately as there could be a serious blockage of the gut or bladder.

How Vets Diagnose the Cause

Physical Exam

Your vet can check your cat’s hydration status and for abdominal pain. They may also be able to feel the backed-up stools within the colon.

Rectal Exam

Sometimes, the vet may be able to feel firm stools or a blockage rectally. However, the blockage may be further inside the colon where the vet can’t reach. The vet can also check the anal glands, and for any growths, foreign material, or other abnormalities that could be causing the problem.

X-rays or an Ultrasound

An X-ray will show the extent of constipation, whether there is a mega-colon, and might show an obstruction. An ultrasound can be useful to check what’s causing the blockage and assess the health of the intestines.

Blood Tests

Blood tests will show dehydration, electrolyte balance, and signs of any underlying conditions, like hyperthyroidism or kidney disease.

Treatment and Management Options

At-Home Relief (only for mild constipation)

• Increase hydration by adding more ‘water stations’, switching to wet food, adding extra water to meals, or using a cat fountain.
• Increase fiber intake with vet-approved fiber supplements or high-fiber cat foods.
• Increase activity levels by encouraging play with new toys and adding playtime with you to their daily routine.
• Avoid hairballs by brushing your cat regularly, especially if they have long hair. You can also give hairball paste products that help the hair to pass without getting stuck.
• Provide more litter boxes (at least one per cat plus one extra) and keep them clean. Find your cat’s preferred litter box style (e.g., covered, shallow, etc.) and cat litter type to avoid any litter box aversion.

Veterinary Treatment (for moderate or severe cases or when mild cases fail to improve)

• Fluids via a drip or by injection under the skin to improve hydration.
• Laxatives and stool softeners like lactulose and Microlax (only to be given under vet instruction).
• An enema or manual stool removal – the vet will usually give sedation or an anesthetic to allow them to use warm fluids and lubricants to dislodge the hard feces.
• Medications to increase peristalsis (used only in mega-colon or long-term cases).

You must never give human laxatives or mineral oil to cats — they can be toxic and may cause aspiration.

Preventing Constipation in Cats

• Encourage drinking and increase water intake.
• Feed wet cat food that’s high quality and high in fiber.
• Consider probiotics, fiber supplements, or other digestive supplements (speak to your vet first).
• Keep your cat at a healthy weight and encourage activity.
• Brush your cat regularly to reduce the risk of hairballs.
• Keep litter boxes clean and accessible.

FAQs

Summary

Constipation in cats is quite common and often due to poor hydration, obesity, lack of activity, or hairballs. Thankfully, mild cases are easily treatable, and further constipation can be prevented with simple changes to your cat’s drinking, grooming, and toileting routine. If your cat hasn’t gone in a day or two, don’t panic, but do pay attention. With the right diet, hydration, and care, most cats return to regular, healthy habits quickly.

Dr. Hannah Godfrey BVetMed MRCVS

Hannah graduated in 2011 and works as a small animal vet in Cardiff, UK. She loves meeting people and their special pets and has a particular interest in diagnostic imaging, soft tissue surgery, and dentistry.

Feature image: istockphoto