A surprising number of cats have problems with constipation (abnormal accumulation of feces and difficulty defecating), and similar but more serious conditions such as obstipation (complete obstruction of the colon by feces) and megacolon (damaged nerves and muscles in the colon causing an inability to defecate). Constipation is uncomfortable, even painful. Constipated cats may defecate (or try to) outside the litterbox, because they associate pain or discomfort with the box itself. Other signs of constipation include irritability, painful abdomen, lethargy, and poor appetite or even loss of appetite.
The colon, the last part of the intestinal tract, is a large muscular structure ending at the rectum. It contains most of the intestinal bacteria that reside in the gastrointestinal (GI) tract. These bacteria finish up the digestion of protein. By-products of this process include short-chain fatty acids that nourish the cells lining the colon. Some of these lining cells absorb water, while others secrete mucus to lubricate the stool and keep it moving along.
Most cats defecate about once a day. A constipated cat may only defecate every 2 to 4 days, or even less. Usually the stools are hard and dry, because their long stay in the colon allows for absorption of most of their water content. However, occasionally a constipated cat can appear to have diarrhea, because liquid stool is the only thing that can get around the stuck mass of feces.
Causes for pooping problems include neurologic problems, pelvic injury, obstruction (by hair, bones, etc.), and Inflammatory Bowel Disease (IBD). A dirty litter box may cause a cat to avoid the box and become constipated by holding the stool too long. Hooded litterboxes are a particular problem because they hold odor in, potentially making the box environment extremely unpleasant for the cat.
In 15+ years of experience as a feline veterinarian, I know of only 2 cats who had constipation problems who do not eat dry food. It’s logical, therefore, to think that diet plays a significant role in development of the problem. Some cats may need more fiber than is present in very low fiber diets such as most canned, raw and homemade diets.You can always add a pinch of fiber (ground flaxseeds and ground chia seeds, aka Salba, are reasonably palatable and work very well).
Indeed, the initial treatment for constipation is usually a change in diet. Historically, these cats have usually been put on high-fiber dry foods. Fiber modulates intestinal mobility. Depending on the type of fiber and the circumstances, fiber can either speed up or slow down digestion. It’s therefore used for both constipation and diarrhea. Light, senior, and hairball foods all contain increased fiber, and there are also several medical high-fiber diets.
Usually the diet change helps, at least initially. However, eventually these foods often seem to lose their effectiveness over time. More fiber, such as canned pumpkin, may be added. Again, sometimes this produces a temporary improvement. Yet most of these cats continue to have problems.
Since fiber encourages water absorption and increases the amount of stool produced (because it is indigestible), many experts have swung the other way and are recommending « low-residue » diets to minimize stool volume. « Low-residue » means that the food is highly digestible and produces minimal waste. Cats digest protein and fat best, but there is controversy about carbohydrates; it is clear that many cats are carb-intolerant. By this theory, the best food would be high fat, high protein, and low fiber, as well as high moisture. One would think that such a food would also be low fiber, but that is not necessarily true. Eukanuba Low Residue dry food contains 4% fiber, which is fairly high. Most canned foods fit this description, as do most homemade. However, Eukanuba Low Residue manages to incorporate a large amount of carbohydrate, even in its canned food. Reading the label is an important skill to develop.
Water balance is crucial in constipated kitties. Most vets will give constipated cats subcutaneous (or even intravenous) fluids to boost their hydration.
Treatment for constipation depends on the severity of the problem. For mild cases, occasional enemas may be all they need. For severe blockages, the cat must be anesthetized for manual extraction of the feces (a process my favorite tech graphically but accurately refers to as a « dig-out »).
Once the cat is « cleaned out » by whatever means, it’s wise to take steps to prevent the problem from recurring. Several options are available; an individual cat may need only one of these, while others need several or all of them.
- Canned or homemade diet. High-moisture diets keep the cat hydrated, and these diets are far more digestible – and produce far less waste – than dry food. Because canned and homemade diets tend to be extremely low in fiber, addition of a small amount of rice bran or powdered psyllium (available in bulk at most health food stores) is helpful.
- Water Fountain. Many cats will drink much more running water than they will ever take from a bowl. There are several types of pet fountains, from « cascades » to « waterfalls » to models that could be from Rome! They are readily available online. Be sure to keep the fountain clean so your cat keeps drinking.
- Lactulose. This is a sugary syrup that holds water in the stool and keeps the stool soft; therefore it’s easier for the cat to pass. Cats are usually not fond of the taste. Fortunately, lactulose now comes in a mild-tasting powder (Kristalose) that can be encapsulated by a compounding pharmacy, or simply added to canned food.
- Other stool softeners, such as DSS (docusate sodium). Your veterinarian can prescribe these.
- Petroleum Jelly. The primary ingredient in most over-the-counter hairball remedies (Laxatone, Kat-a-lax, Petromalt), petroleum jelly can be given to the cat by mouth. Most cats tolerate it, many cats come to like it, and a few even enjoy it. The Vaseline brand is, according to my cats, the tastiest; but other cats prefer one of the flavored hairball types. Give 1/3 to 1/2 teaspoon per day. It can also be mixed with a small amount of canned food. However, it can interfere with nutrient absorption so giving it on an empty tummy is best.
- Cisapride (Propulsid). This drug was withdrawn from the market for humans because of dangerous side effects, but it is considered safe for cats. Your vet can order it from a compounding pharmacy. It seems to work best in combination with stool softeners.
- Pediatric glycerin suppositories. Although they may not appreciate having a suppository pushed into their rectums, most cats tolerate it. Your vet can advise you on technique and frequency.
- Enemas. Many cat guardians have gotten good at giving enemas at home. Mineral oil, K-Y jelly, soapy water, and plain warm water are all fine; you may have to experiment to see which one works best for your particular cat.
- Slippery Elm Bark or Marshmallow. These herbs can be added to canned food (add extra cool water) or made into a syrup. Their mild taste is well tolerated by most cats. They form mucilage, a slippery substance that helps move the intestinal contents along. There are many herbal formulas available for people, but many herbs, such as Cascara sagrada, are too harsh for a cat.
- Exercise. Staying active helps stimulate the intestines and keep things moving. If your constipated cat is also a couch potato, try Play Therapy for Cats.
- Stress Management. There is always an energetic or emotional component of any chronic disease, and stress plays a significant role in many gastrointestinal conditions. Flower essences are helpful for changing the energetic underpinnings of constipation and other GI diseases.
- Fluid Therapy. Some cats do very well with occasional (daily to weekly) infusions of subcutaneous fluids. Your veterinarian or vet tech can show you how to do this at home. Give fluids whenever you notice your cat’s behavior indicate oncoming constipation.
- Surgery. If there is damage to the nerves and muscles of the colon, a « sub-total colectomy » is the last resort. This surgery removes the colon, and joins the small intestine to the rectum. Unless and until the small intestine develops more colon-like functioning, the result is chronic diarrhea. However, the cat will be much more comfortable.
If your cat is chronically constipated, the most important thing for you to do is be observant. Look for early signs of constipation; straining, abdominal discomfort, decreasing appetite, etc. Be aware of how often the cat is defecating. If he does not produce adequate stool for more than 2-3 days, call your vet, or begin home treatments if you have established this routine. Kitty constipation is far easier to treat when it’s caught early. If you wait, treatment will be far more expensive, and there is a greater chance of irreversible colon damage.