If you’ve ever suffered from constipation, you know how uncomfortable it can be. In small animal practice, cats develop constipation a lot more frequently than dogs. Most cats who suffer from constipation develop this problem as they get older due to medical problems that promote fluid losses and dehydration. Some younger cats with underlying anatomic problems may develop constipation problems too. The good news is there are a lot of ways you can help keep your cat regular by incorporating a variety of simple adjustments.
The key to preventing constipation in your cat centers around the right home plan. A home plan to prevent feline constipation includes providing the right diet, ensuring hydration, incorporating laxatives, weight and exercise control, and stress reduction.
Purina’s Hydracare is a tasty liquid gel that is nutrient enriched and was created to increase hydration in cats.
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Read on to learn more about causes for feline constipation and proven home remedies you can incorporate at home to keep your cat regular.
An over the counter laxative that I recommend most often for my feline patients is called Miralax. This comes as a powder that you can mix with the liquid from saucy canned food. It is tasteless and well accepted by cats. A typical dose is 1/8th to 1/4th of a teaspoon 1-2 times per day. The amount should be titrated to effect based on the quality of the stool in the litterbox. It is available on Amazon.
Reasons for constipation in cats
Dehydration. This is the most common cause of constipation. Older cats frequently develop kidney disease as they age. This can be a common culprit for developing constipation because kidney disease first affects the body’s ability to conserve water. This means cats with kidney disease produce a lot more urine and these fluid losses can lead to global dehydration.
Other medical issues that can lead to dehydration are diseases like hyperthyroidism and hypercalcemia which both cause increased urination.
Chronic vomiting, diarrhea, or decreased water consumption secondary to illness, medications or other conditions that lead to decreased water consumption such as nausea, lack of easy water access, or oral diseases.
Orthopedic diseases such as arthritis which can make posturing to defecate difficult, or a previous pelvic fracture which fused causing a narrowed pelvic canal.
Neurologic dysfunction from intervertebral disc disease or any other disease which affects posture and balance can create trouble with posturing to defecate easily. Abnormal innervation of the smooth muscles of the colon from malformation of the caudal spine.
Excessive stool volume from a diet too high in fiber
Genetic causes in some cats such as the Manx breed suffer from abnormal innervation to the colon because of caudal spinal malformations. These cats can develop megacolon which causes generalized weakness of the muscles of the colon and dilation of the colon.
Medications can cause constipation. Examples are opiate pain relievers, anticholinergic drug, and diuretic drugs.
Environmental stressors such as litter box location, litter box coverings, litter type or inter-cat aggression by the litter box. Household changes such as guests in the home, owners who vacation, or change in routines can also trigger stress.
Changes to the colon: masses within the colon, or a mass outside the colon compressing the organ, intussusception, hernias, and idiopathic megacolon can all cause constipation
Controlling constipation in cats
Once your cat is constipated it is much more difficult, but not impossible, to manage their condition at home.
The three main tenets to preventing constipation in a cat is to feed a low residue diet, encourage proper hydration, and use a daily laxative to keep stool soft.
A low residue diet is a non-bulking and highly digestible diet that is lower in fiber than other foods. This means that the food you cat eats is digested easily and produces less waste (in the form of stool).
Cats prone to constipation should be fed only wet foods and this food ideally should be watered down a bit to make it more soupy to increase your cat’s water consumption. Some cats are addicted to dry food. If your cat battles severe constipation but won’t eat wet food, a successful transition can happen by incorporating daily appetite stimulants such as mirtazapine to promote their desire to eat a different food. In a few weeks to months, your cat can probably be weaned off this medication.
One of the best daily laxatives is also the easiest to give and available without a prescription: Miralax. This is a tasteless powder that is easily mixed into moist food.
The best low residue diets for cats are the following prescription diets
- The Iams Low Residue canned is a low fiber diet, highly digestible
- Purina Pro Plan Veterinary Diet Gastroenteric EN and EN Naturals canned
- Hill’s Prescription Diet i/D canned, also i/D Chicken and Vegetable Stew
- Royal Canin Veterinary Gastrointestinal Food (formally GI High Energy)
If prescription food is not an option, then canned kitten food is going to be the lowest in overall fiber.
The truth about fiber for constipation in cats
Fiber is a supplement that has many benefits for the colon. It feeds the good colonic bacteria which in turn helps keep the colonic cells healthy and supports the neuronal function that stimulates the movement of the colon. Increasing fecal volume with fiber can stimulate the bowels and promote pooping. However, for many cats, a high fiber diet may end up being too bulky and lead to constipation.
Cats that have mild constipation problems can benefit from fiber supplementation. But, in my experience, cats with more long standing constipation or an underlying condition like megacolon will not benefit from excess fiber.
How do you know if your cat is in danger of developing constipation?
Knowing how to monitor your cat’s stool quality is one of the key ways to understand if your cat is at risk for developing constipation.
A normal healthy stool is in the shape of a log and is moist enough to have litter attached to the stool. Feces which are too hard and dehydrated will look more like fecal balls or pellets. The consistency can be clay like. Purina makes a helpful fecal scoring chart.
Constipated cats may visibly strain to pass stool and may pass stool outside the litterbox. They may vomit from the effort to push out the hardened feces. The irritative effects of the hard feces in the colon may cause blood or mucus to pass with the feces.
Some cats have a genetic predisposition to having bowel problems. These are typically in the Manx breed because they have shortened or absent tails with irregular caudal spinal conformations. Some of these cats may have abnormal nervous system innervation of the smooth muscles of the colon predisposing them to having a flaccid dilated colon called megacolon
Prescription veterinary foods best for constipated cats and how much to feed
The average 10 lb cat requires about 180 to 200Kcal per day, which is generally about 1 ⅓ to 1 ½ cans per day
- Iams Low Residue: 160 kcal/can
- Science Diet I/D : 161 kcal/can
- Proplan EN : 151 kcal/can
- Royal Canin Gastrointestinal food (formerly Gastrointestinal high energy): 180 kcal/can
Tips to improve your cat’s hydration and reduce constipation
Increase water consumption in cats
- A Water fountain. Cats love moving water, so water fountains attract cats to drink naturally
- Hydracare by Purina. This product is a great new invention to promote hydration in cats. It is an osmolyte enriched gel that is chicken flavored and when consumed by cats increased their hydration by 50% over cats that just drank water
- Wet food diet: feeding an all wet food diet will make sure your cat consumes more moisture
- Add tuna juice or clam juice to water sources to improve the palatability
- Subcutaneous fluid administration. This method is only for cats prescribed this treatment by their veterinarian to improve hydration. It involves using a needle to deliver a small bolus of electrolyte enriched sterile saline underneath the skin. This is most often prescribed to cats in kidney failure.
Give probiotics which can reduce constipation in cats
A study of cats with megacolon and constipation previously not responsive to medical management were given a European multi-strain probiotic daily for 3 months. These cats did not have relapses of constipation and maintained regular bowel movements. The probiotic is most similar to a veterinary probiotic called Visbiome (available on Amazon) and was dosed at 200 billion CFU’s per daily dose (2 capsules of the 112.5 billion/capsule Visbiome capsules per day)
Probiotics work by improving the gut health of the colon, reducing colon inflammation and improving neurologic function of the colon.
Brush your cat often
This is particularly important in longer haired cats who groom and ingest a lot of hair which can create impacted and firmer feces.
Reduce stress with litter box management , supplemental products, exercise and weight control
Litter box management
Key tenets to reducing feline stress are to create many zones in the home for perching, playing, feeding, and elimination. These zones should be separated. The recommended number of litter boxes is one more than the number of cats in the home. Aggression and ambush can happen frequently around litter boxes, so providing non-hooded boxes, and multiple boxes is important. Ideally a litter box should be 1 ½ times the length of the cat. Providing a litter that is pleasing to your cat may require trial and error with different brands. Finally, some cats that are reluctant to use the litter box may prefer a litter called Cat Attract which contains natural herbs to entice cats to utilize the box.
Stress reducing products
Feliway: This is a calming feline pheromone that comes as a diffuser and spray. The Multicat is designed to reduce inter-cat aggression and is available on Amazon. The Classic Feliway is to reduce anxiety in cats and is available on Amazon.
Zylkene: This is a calming supplement that comes as a tasteless powder inside a capsule. The Zylkene capsule is to be opened and mixed into food daily. Available on Amazon.
Exercise and weight reduction
Cats that exercise and are lean are less likely to develop constipation. It is recommended to play with your cat daily with toys that promote movement (feather toys, laser pointers). Some indoor cats really enjoy exercise wheels.
Count your cat’s calories and stick to a regular diet. The average 10 lb cat only requires between 180 and 200 Kcalories per day.
Using laxatives in cats
Laxatives in cats are either bulk-forming, lubricant, osmotic or stimulant.
Bulk-forming laxatives rely on added fiber to increase stool volume which then can stimulate a bowel movement. This can be useful in mild cases but in chronic constipation may worsen the problem.
Lubricant laxatives help to lubricate the stool to help it pass. It also is best used in milder cases or as an adjunctive treatment.
Osmotic laxatives are by far the most regularly utilized laxatives. Osmotic laxatives work by drawing water into the bowel to soften the stool. My favorite laxative is the osmotic laxative Miralax. It is a polyethylene glycol powder available without a prescription . It is a tasteless powder that is easily mixed into moistened food or water. Another popular osmotic laxative is
Finally, there are stimulant laxatives available. These should be recommended by your veterinarian before use and should be incorporated after other methods have been tried. Stimulant laxatives cause cramping as they stimulate the bowels to move. They are contra-indicated for any cat suspected of having a bowel obstruction and these stimulant laxatives can cause vomiting and nausea and discomfort. They are most commonly recommended in cats with weak bowel function (megacolon).
Examples of laxatives for cats
Bulk-forming laxatives
Add to moist cat food. Only for use in mild cases
Psyllium (1-4 tsp per meal)
Benefiber (Give 1/4 to 1/2 teaspoon twice a day
Lubricant laxatives
Laxatone Hair Ball remedy: contains white petrolatum and light mineral oil (1-5 ml orally every 24 hours). Available on Amazon.
Vaseline or Petroleum jelly (Give a 1/2 teaspoon orally twice a day)
Osmotic laxatives
Lactulose (1-3ml orally every 8 to 12 hours)
Miralax PEG (1/4–1/2 tsp twice a day in canned food
Stimulant laxatives
Bisacodyl (Dulcolax) not recommended for use without a veterinarian recommendation. Contraindicated in animals with a possible GI obstruction
When to bring your constipated cat to the vet
Cats that remain constipated for longer than 3-4 days should be seen by your veterinarian. These cats may require enemas to evacuate their bowels. Labwork and abdominal x-rays may be performed to assess your cat’s hydration, electrolyte balance and screen for any metabolic diseases such as chronic kidney disease. Abdominal x-rays are very useful to assess the severity of constipation, the degree of dilation of the colon, screen for any orthopedic impediments to defecation or masses within the abdomen. The x-ray below shows a very constipated cat whose entire transverse and descending colon is dilated with feces. The colon is distended about twice it’s normal diameter.
Enemas in cats
Enemas used in cats are typically made of either warm water or warm water mixed with mineral oil or Dioctyl sodium succinate.
For more severely constipated cats that cannot evacuate their bowels with traditional enemas, a nasogastric tube is placed for a slow trickle of PEG 3350 (GoLytely, CoLyte) osmotic laxative therapy. This high molecular weight soluble polymer binds water and prevents absorption across the intestines. Defecation typically occurs 6-12 hours later. It must only be administered to a cat that has been well hydrated with intravenous fluids first.
The diameter of the colon on the lateral view should be approximately the same length as the body of the 2nd lumbar vertebrae.
A last resort option for cats that are refractory to medical therapy is a surgical procedure called sub total colectomy. This is a surgery to remove the non-functioning part of the colon. It is most often performed in cats with chronic colonic dilation and lack of neurologic function of the smooth muscles of the colon. Cats have a generally favorable prognosis for recovery following colectomy, although mild to moderate diarrhea may persist for weeks to months postoperatively in some cases.