Mr. Kitty was an older cat that suffered from chronic constipation for years. I’ll never forget his sad face when he came to the clinic to have his stool manually removed every couple of weeks. Back then most vets believed the only and best cat foods for constipation were the high fiber ones we also prescribed for weight loss.
As a general rule, these days veterinarians recommend pet owners try different dietary approaches to see which works best. The four recommended categories of food for constipated cats are:
Wet food is always recommended over dry food. 2 to 4 weeks of feeding is usually long enough to know whether a particular product helps your cat’s bowel regularity.
Systematic Food Trial for Your Constipated Cat
It’s impossible to know which food is best for your individual pet without trying it for a couple of weeks. Some do better with high fiber foods while others thrive on low-carb diets.
As for how to choose which food to try first, start with wet cat food that’s higher in fiber than the current food. You can use dry kibble with similar qualities if you absolutely have to.
If there is no improvement after 2-4 weeks of eating 100% of the new food, move on to low residue cat food (with average or low fiber) for 2-4 weeks. If that one fails to get things moving, a hypoallergenic prescription diet (with average or low dietary fiber) is the next stop in this experiment.
To summarize, the best cat foods for constipation are preferably a wet (canned) version of food from one of the four categories mentioned above. Change to the new food gradually over 7 days and continue feeding it for at least 2-4 weeks.
Vet-Recommended Foods for Cat Constipation
We are fortunate to live in these times with a huge number of pet food products from which to choose. It does make it a bit overwhelming to choose just one, though. This article should give you a decent list of products to try.
I’ve chosen one standout product in each category, but there are lots of other choices. I’ve evaluated a bunch of foods to find some good options. I looked at a few criteria: macronutrient ratio (carbs 15% or fewer desirable), dry or wet form, prescription or over-the-counter, widely available vs. regional, cost per calorie, manufacturer track record for producing high-quality and safe food.
Choose one food from the following categories and feed it for a full 2-4 weeks before trying a different one. I recommend starting with high fiber, then low carb, then highly digestible and finally hypoallergenic food.
Cat Food with High Fiber
With product labels being so vague, you need to keep an eye out for certain terms manufacturers use to indicate high fiber. Some of the buzzwords to look for on labels that probably mean the food is high in fiber are:
- Hairball Control
- Indoor Cat
- Weight Control
These formulas often contain more fiber than average. They may also contain fewer calories, which is great if your kitty is overweight but not great if your he is normal weight or too skinny. If your cat doesn’t need to lose weight, check the calorie count and make sure you’re feeding enough to maintain.
High Fiber Wet Food: Blue Buffalo Healthy Gourmet Adult Pate Indoor Chicken Entree
(Protein 39%, Fat 57%, Carb. 4%; Crude Fiber 9% Dry Matter)
Pros: low in carbohydrates, higher in fiber, includes soluble fiber sources like flaxseed and guar gum,
Cons: quite high in fat-might bother a sensitive cat, only 2 flavors: chicken and salmon, only available in pate form, relatively lower cost, available at grocery and pet supply stores, etc.
High Fiber Dry Food: Blue Buffalo Wilderness High Protein Grain Free, Natural Adult Indoor
(Protein 36%, Fat 37%, Carb. 27%; Crude Fiber 7% Dry Matter)
Pros: Relatively lower in carbs for dry food at 27% of calories, higher in fiber at 7% dry matter, includes soluble fiber sources like peas and flaxseed, grain-free for sensitive cats, low cost and convenience of dry food.
Cons: relatively lower cost, available at grocery and pet supply stores, etc.
High Fiber Wet Food: Purina Pro Plan Veterinary Diets OM Overweight Management Savory Selects With Turkey
(Protein 53%, Fat 30%, Carb. 17%; Crude Fiber 7% Dry Matter)
Pros: Only 17% of calories from carbs, high fiber, high protein.
Cons: soluble fiber content may be lower based on ingredient list, prescription only, cost is higher than non-rx food, may have to special order.
High Fiber Dry Food: Hill’s Prescription Diet Gastrointestinal Biome Digestive/Fiber Care
(Protein 35%, Fat 16%, Carb. 35%; Crude Fiber 8% Dry Matter)
Pros: contains both soluble and insoluble fiber, prebiotics, lower cost than prescription canned food
Cons: high in carbohydrates, cost, need a prescription, may not be available as canned food, limited to one flavor and texture, vet may have to special order the food or write you a prescription to get it elsewhere
Low Carbohydrate Cat Food
When it comes to low carbohydrate food, it’s difficult to tell which ones are and which ones aren’t. In general, dry foods are hardly ever low-carb. Canned foods may or may not be. Don’t be fooled into thinking grain-free formulas are necessarily low-carb because they usually contain starches to replace the grain.
If you’re looking for a low-carb canned or raw food, the best resource for you is Dr. Pierson’s food list at catinfo.org. Try to find one that has less than 15% of calories from carbs on that list (there are many options).
She doesn’t list any dry foods because they’re not ideal for overall health. Also, there aren’t very many dry cat foods that have a low carbohydrate level. I’ve listed a couple in the chart that you can use if you absolutely cannot get your cat to switch to canned food.
Low Carb Wet Food: Weruva Grain-Free Natural Canned, Classic Recipes
(Protein 65%, Fat 32%, Carb. 3%; Crude Fiber 3% Dry Matter)
Pros: Low carbohydrate level at 3% of calories coming from carbs, grain-free, moisture content is especially high at 85% of dry matter, high protein, the fat level is not extremely high like some low-carb foods, no prescription needed.
Cons: very high cost for non-prescription food, may be difficult to find (try ordering online).
Low Carb Dry Food: Young Again 50/22 Premium High Protein
(Protein 44%, Fat 44%, Carb. 8%; Crude Fiber 3% Dry Matter)
Pros: one of the only non-prescription low carb dry cat foods available in the US at this time, low in carbs at about 8% of calories, great for dry food addict cats, contains multiple fiber sources including soluble fiber, no prescription needed, relatively low cost, free shipping on orders over $30.
Cons: low moisture level, smaller family-owned company doesn’t have the reputation of the larger companies, contains small amounts of potato starch, only available on the YoungAgain website.
Low Carb Wet Food: Purina Veterinary Diets DM Dietetic Management
(Protein 43%, Fat 52%, Carb. 6%; Crude Fiber 5% Dry Matter)
Pros: low carb level at 6% of calories, moist food, cats like the flavor, relatively inexpensive for prescription canned food, contains multiple fiber sources including soluble fiber.
Cons: higher in fiber than many low carb canned foods may be a problem for some cats, only available by prescription, may need to special order from a vet or buy online
Low Carb Dry Food: Veterinary Diets Purina Pro Plan DM DM Dietetic Management
(Protein 52%, Fat 37%, Carb. 11%; Crude Fiber 3% Dry Matter)
Pros: only 11% of calories from carbs, high in protein, formulated to prevent bladder stones.
Cons: low moisture level, contains several highly processed ingredients, relatively high in fat, higher fiber level than average-may cause problems for some cats, relatively expensive for prescription food, prescription-only and may have to special order from your vet or buy it online.
Highly Digestible/Low-Residue Cat Foods
Ingredients of the products in this category have been processed in such a way that they’re easy for the digestive tract to break down and assimilate. Low-residue diets are also designed with a low fiber level.
Some pet food manufacturers do digestibility studies, especially for prescription low-residue foods. But most commercial formulas are not analyzed this way.
Without this testing, we can really only guess at how digestible a given recipe is based on its ingredients.
Therefore, I strongly recommend using a prescription low-residue food for this step of your experiment. If you absolutely cannot do that, here are some of the key phrases to look for on labels on non-prescription products:
- Sensitive Stomach/Skin
- Low Residue
Highly Digestible Wet Food: Iams Grain Free Chicken
(Protein 39%, Fat 49%, Carb. 12%; Crude Fiber 5% Dry Matter)
Pros: grain-free, low/average fiber level 5% maximum of dry matter, low carb at 12% of metabolizable energy, non-prescription, simple ingredients–mostly chicken, wet food.
Cons: higher cost for an OTC product, not a good option if your kitty has issues with chicken.
Highly Digestible Dry Food: Purina ONE Sensitive Skin & Stomach
(Protein 34%, Fat 15%, Carb. 34%; Crude Fiber 2% Dry Matter)
Pros: low cost, the convenience of dry food, low/average fiber, moderate fat, no prescription necessary, widely available, cats like it.
Cons: highly processed, contains grains, low fat/high carbohydrate content.
Highly Digestible Wet Food: Hill’s Prescription Diet m/d GlucoSupport
(Protein 46%, Fat 41%, Carb. 13%; Crude Fiber 3% Dry Matter)
Pros: available as wet or dry food, lower carb level at 13% metabolizable energy, lower fiber level at 3% of dry matter, formulated to help with weight loss
Cons: requires a prescription, your vet may have to special order it, higher cost, limited flavors and textures
Highly Digestible Dry Food: Purina Pro Plan Veterinary Diets EN Gastroenteric Naturals
(Protein 47%, Fat 17%, Carb. 19%; Crude Fiber 6% Dry Matter)
Pros: Low carb content for dry food at just about 18%, high in calories means you don’t have to feed as much and makes the overall cost lower, highly digestible (proven with testing), helps prevent urinary crystals, contains omega fatty acids (fish oil), cats seem to love the flavor.
Cons: prescription only, only one flavor available, highly processed, dry food.
Hypoallergenic Cat Food
I don’t recommend non-prescription products for cats who truly need to go through a hypoallergenic food trial. The reason is that I don’t trust that the ingredients are strictly controlled enough to make the food trial accurate.
For a legitimate hypoallergenic food trial, prescription food is well worth the extra money. If you’re going to go through the hassle, you might as well do it right the first time.
If you just want to try changing protein sources, you can do this by choosing a non-prescription product that claims limited ingredients. Rabbit, duck, and pheasant are novel protein sources that work well for cats.
Hypoallergenic Wet Food: Natural Balance L.I.D. Limited Ingredient Diets Duck and Green Peas
(Protein 31%, Fat 58%, Carb. 11%; Crude Fiber 9% Dry Matter)
Pros: wet food, grain-free, only one protein source that is likely to be novel to your cat, available over the counter, the price per calorie is moderate.
Cons: not the gold standard for a hypoallergenic diet–may contain trace amounts of other proteins, has a high fat content (58%) which could irritate a sensitive stomach, peas are a controversial ingredient, some cats might not like the flavor.
Has a higher fiber level at 9% which could be favorable or unfavorable depending on the cat.
Hypoallergenic Dry Food: Natural Balance L.I.D. Limited Ingredient Diets Duck and Green Peas, Grain Free
(Protein 30%, Fat 29%, Carb. 41%; Crude Fiber 4% Dry Matter)
Pros: grain-free, widely available, low cost compared to prescription diets.
Cons: not the gold standard for food allergy trials (may contain traces of other proteins), high in carbs at 41%, relatively high cost for non-prescription food, dry form, some cats might not like it.
Hypoallergenic Wet Food: Royal Canin Veterinary Diet Selected Protein Adult PD in Gel Canned
(Protein 31%, Fat 53%, Carb. 16%; Crude Fiber 11% Dry Matter)
Pros: low carb content at 16%, moist form but also available in dry, somewhat less processed than hydrolyzed diets, cats seem to like it.
Cons: peas are the first ingredient, high cost, prescription only.
Hypoallergenic Dry Food: Royal Canin Ultamino
(Protein 23%, Fat 35%, Carb. 42%; Crude Fiber 6% Dry Matter)
Pros: many vets consider this the gold standard for food allergy trials, works well for food allergy.
Cons: highest cost among the hydrolyzed dry diets I reviewed, prescription only, dry form only, some cats might not like it.
Does Switching Cat Food Cause Constipation?
Changing food too quickly can confuse the beneficial organisms living in your cat’s guts. You could see a worsening constipation or even diarrhea with sudden food changes.
Remember, always change your cat’s diet gradually over 7 to 10 days to allow your cat’s GI microbiome to adjust.
Feed the new food for at least two weeks before drawing a conclusion about whether the litter box problems are better, unchanged or worse.
How to Choose the Best Cat Food for Constipation
Choosing the perfect food for your cat might take some trial and error. I looked at dozens and dozens of prescription and non-prescription cat food products in search of the best options to recommend to my clients and readers.
In this section, I’ll outline the specific characteristics looked for when considering which foods to recommend. You can use these same criteria if you want to use something that is not on my list.
Ideal Moisture Content for Constipated Cats
A constipated cat should eat moist food with at least 70% or more moisture on the label’s guaranteed analysis. You can choose canned cat food, frozen raw cat food or make a balanced homemade recipe.
Here I go again discussing why cats should eat a high moisture diet.
Domestic felines are descended from desert-dwelling creatures whose physiology makes them great at conserving water. At the same time, we now know that a cat’s body sends thirst signals based on the dry matter content of food rather than the moisture content of the food.
Put in simpler terms, cats eating low-moisture dry food don’t drink more water to make up for the moisture lacking in the food. They just don’t get thirsty. Cats who eat canned cat food end up taking in quite a bit more moisture (because it’s mixed into the food) than cats who eat dry cat food.
In the real world, we have cats who are so habituated to dry food that switching is very difficult. You can feed dry cat food, but your kitty might not have as good an outcome as with wet food. If you must feed dry kibble, take extra steps to encourage more liquid intake like adding broth, using a water fountain, etc.
How Much Carbohydrate Is Best for Hard Cat Stool?
Many veterinary specialists find a low-carb diet benefits many health conditions, including cat constipation. Look for products that contain 15% or fewer calories from carbohydrates. A lower percentage, like under 10%, may be necessary for some animals.
Felines are obligate carnivores, meaning they require nutrients that are only found in animal-based diets. Animal-based food, i.e. meat, contains little to no carbohydrate.
That’s not to say that all kitties do poorly while eating carbohydrates. But they’re not evolutionarily set up to thrive on a diet based on rice, potatoes and peas.
Too bad it’s such a challenge to figure out which foods are high-carb and which aren’t! Current labels don’t require carbohydrate content to be displayed, but it can be roughly calculated based on the label’s “guaranteed analysis.”
When I send my clients out to look for an over-the-counter low-carb diet, I send them to Dr. Lisa Pierson’s list at catinfo.org. She has listed the carb content on dozens of foods.
Ideal Fiber Content for Cat Digestion
Some cats with sluggish bowels do better with a lot of dietary fiber while others get worse.
For one thing, they did not evolve to eat lots of plant fiber. In fact, cats don’t require any fiber in their diet. However, a small amount of fiber (5% of dry matter or less) is beneficial to colon health. For another thing, not all fiber is created equal in terms of how the digestive tract reacts to it.
Most pet food labels list only crude fiber maximum percent. This is a very inaccurate measure of the total dietary fiber in the product, often underestimating the amount. Unfortunately, it’s hard to accurately compare one product to another using crude fiber.
Soluble vs. Insoluble Fiber
Included in the crude fiber quantity are the two main types of dietary fiber: soluble and insoluble. Unfortunately, typical pet food labels do not list soluble and insoluble fiber quantities.
If a product claims to be “high fiber,” that usually means high in insoluble fiber (1). You’ll have to check the ingredients to make a guess as to how much soluble fiber is in the ration. Here are some common ingredients to look for:
|Soluble Fiber Ingredients||Effect on a Constipated Cat’s Stool|
|Pectin||Moistens and decreases bulk|
|Citrus Pulp||Moistens and decreases bulk|
|Guar Gum||Moistens and decreases bulk|
|Soy Fiber||Moistens and decreases bulk|
|Inulin||Moistens and decreases bulk|
|Insoluble Fiber Ingredients||Effect on Stool|
|Beet Pulp||Moistens and increases bulk (larger stools)|
|Cellulose||Moistens and increases bulk (larger stools)|
|Pea Fiber||Moistens and increases bulk (larger stools)|
|Rice Bran||Moistens and increases bulk (larger stools)|
Soluble fiber can help many cats with difficult bowel movements. This type of fiber can be dissolved in water and comes from plant foods like psyllium husk, oats, beans and peas. In commercial diets, soluble fiber ingredients include pectin, citrus pulp, guar gum, soy fiber or inulin.
Soluble fiber increases water content in feces but decreases bulk. It forms sort of a gel in the GI tract, lubricating feces so they’re easier to pass. The other great thing about soluble fiber is that it feeds the good bacteria in your cat’s GI tract, acting as a “prebiotic.”
Insoluble fiber does not dissolve in water and is found in things like whole grains, wheat germ, and vegetables. In commercial food, insoluble fiber ingredients include beet pulp, cellulose, pea fiber and rice bran.
Insoluble fiber retains water in feces but also causes it to be bulkier. This kind of fiber can help in some cases, but cats with decreased intestinal tract contractions often do worse with bulkier feces.
Ideally, you’d feed a diet with a balance of soluble and insoluble fiber. Again, these numbers are not listed on cat food labels, so it’s impossible to choose the best one without calling the manufacturer for more information. You might just have to make a guess and experiment to see how your pet reacts.
Too Much Fiber: Side Effects
Too much fiber added too fast can cause digestive tract cramping, diarrhea and excessive gas. Excessive soluble fiber eaten over a long period of time can interfere with absorption of important minerals in the diet.
Add fiber to the diet slowly and gradually increase the amount over several weeks’ time. If your cat is currently eating food with 2% crude fiber, you might change to a food with 5% crude fiber rather than jumping directly up to 7% crude fiber.
Fiber and Megacolon
Finally, consult with your veterinarian if your pet has megacolon (or even chronic severe constipation). High fiber cat food can make things worse if your cat’s colon is unable to have normal contractions. These cats tend to do better with highly digestible diets.
I remember learning about digestibility in my first animal nutrition class. I was surprised to hear that two diets made from essentially the same ingredients might give an animal very different levels of nutrition.
Different parts of the same basic ingredient are easier to digest than others. For example, chicken muscle is easier to digest than chicken by-product which may contain a lot of “gristle.”
Ingredient processing and combination also affects digestibility. It’s harder for an animal to absorb nutrients for raw meat than from cooked meat. Cooked, ground rice is easier to digest than raw, whole rice. And high fiber content decreases the overall dry matter digestibility of a food formulation (1).
Overall, veterinarians find low-carbohydrate, animal protein-based meals are better for most cats. Look for ingredient lists without a lot of plant and starch items like peas, potatoes and lentils. The food might also say it’s good for cats with sensitive stomachs.
We have a plethora of prescription cat foods that are formulated for high digestibility. They often contain a higher level of carbohydrates and are not exactly what you’d call natural. Still, they work miracles for some cats, so don’t turn up your nose at them until you’ve tried them.
Palatability (Tastes Good)
Palatability is not a big problem with most dry foods. Manufacturers figured out a long time ago that they can spray concentrated flavoring on the surface of just about anything and cats will eat it. I think that’s part of the reason cats get addicted to dry cat food–it’s like kids eating Doritos and not wanting to eat an apple because it doesn’t taste as good.
If your kitty is a dry food addict, switching to canned or wet cat food might take some ingenuity. One easy trick is to sprinkle Purina FortiFlora® on the canned food. It has a concentrated animal protein-based flavoring that cats love.
Even the best canned food won’t help your cat’s constipation if it’s not eaten. But it’s not always because it tastes bad. It could just be due to a strong habit formed by eating kibble since kittenhood.
Check out Dr. Pierson’s tips to get dry food addicts to switch to wet food. Be patient, it is possible to out-stubborn your furry friend without starving her.
Price and Availability
There is a huge spectrum of cat food available at different price points. If your cat has a serious constipation problem, your vet might recommend prescription food. Most prescription products are a lot more costly than grocery store brands. But if it saves you trips to the vet, the cost will be well worth it.
Non-prescription cat food appropriate for cat constipation is available anywhere you can buy pet products. There are good choices at both grocery stores and pet supply stores. These days you can get just about any pet product delivered to your door by ordering online.
There are also many choices of prescription nutritional products for more severe feline constipation these days. Your veterinarian will be able to make a recommendation based on your cat’s unique situation. Prescription cat food is often available at your vet’s clinic and also from online retailers with an OK from your vet.
Treats for Cats with Sluggish Bowels
Unless your vet has prescribed a very strict elimination/food allergy diet, it’s OK to give one to three small treats per day. Avoid high carbohydrate treats and opt instead for high-protein natural treats.
Bonito flakes are called “kitty crack” by some because kitties go crazy for them. These are simply dehydrated fish flakes. They’re small and have a low calorie count.
Dehydrated chicken hearts are a great option for cats who don’t like or can’t tolerate fish. You can also try dehydrated chicken liver, but don’t give more than a couple of ½ inch pieces each day since they’re high in vitamin A.
Cats on a specific hypoallergenic diet can be given pieces of their kibble for treats. There are a few hypoallergenic treats available, but ask your vet before using these. They could mess up a very strict diet trial.
Non-Food Factors to Help Cat Bowels
When choosing a new diet to help your cat’s bowels, consider the current diet. Look at how much crude fiber it contains, what the protein source is, and what the moisture level is. With any new diet, you need to change at least one of those factors and do a feeding trial for a couple of weeks.
Meal Size and Frequency
You should also think about how often your cat is fed. Smaller, more frequent meals may help increase contractions in the lower digestive tract.
When thinking about how much they’re fed, be realistic about their access to treats and other foods. If they’re eating more than one or two very small treats each day, make sure you use one that “matches” the food you’re feeding.
Cats are naturally fastidious animals. They want a litter box that is private, quiet, conveniently located and clean.
A senior feline might do better with a low-edge entry box. Consider putting a box on each level of your house, too.
Provide one more litter box than the number of cats living in your home. Two cats should have at least three litter boxes.
Scoop all boxes daily and dump and scrub with soap and water weekly. But be careful about changing locations or the type of litter you use because some cats are very particular about their potty!
Exercise immediately after meal time may also improve your cat’s digestion. So if your kitty is in the habit of laying about in a “food coma” after eating, get out the toys and get him moving for 15 to 30 minutes.
Be honest about your pet’s weight status, does he need to lose weight? Obesity is a big risk factor for cat constipation. You might need to use a diet formulated for weight loss but at the very least feed no more than the amount recommended on the product label. You might want to weigh out each meal on a kitchen scale since a few extra grams of food can make a big difference to an animal that only weighs around 10 pounds!
Looking for more Cat Constipation Remedies? Click to Read My Other Article…
Dietary Supplements to Ease Bowel Movement
There are many, many supplements offered for every cat ailment you can possibly imagine. Most don’t cause harm, but waste your money and might cause hard feelings between you and your cat if they don’t want to take them.
Supplements that are worth a try include probiotics. Some foods contain extra probiotics, but I think it’s worthwhile to try adding some to your cat’s food. I recommend either Proviable DC which is flavorless or Purina Fortiflora which is considered absolutely delicious by most cats. Use the supplement for at least a month before you decide whether or not it’s helping.
Adding natural food-based fiber to wet cat food can work well for some. Canned pumpkin has 28% crude fiber on a dry matter basis (1). A tablespoon or two per day is probably the maximum amount most cats will tolerate before they refuse to eat.
Psyllium husk (a.k.a. Metamucil) is a fiber supplement for humans that contains both soluble and insoluble fiber. Add ¼ teaspoon to meals one to three times per day. These are not recommended for long-term use as they can interfere with mineral absorption.
- Hand MS, Thatcher CD, Remillard RL, Roudebush P, eds. Small Animal Clinical Nutrition, 4th ed. Marceline, MO: Mark Morris Institute; 2000:725-881.
- National Research Council (2006, July 24). YOUR CAT’S NUTRITIONAL NEEDS A Science-Based Guide For Pet Owners. Retrieved February 10, 2021, from https://www.nap.edu/resource/10668/cat_nutrition_final.pdf
Last update on 2021-07-28 / Affiliate links / Images from Amazon Product Advertising API