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Home > Cats > 5 Hairball Cat Food Side Effects You Need to Know

5 Hairball Cat Food Side Effects You Need to Know

Gray cat eating from the bowl

Unfortunately for cat owners, hairballs are a common sight when it comes to our hygiene-conscious felines. Caused by their admirable attempts to keep themselves clean, hairballs are a frequent and icky issue we have to keep an eye on.

Luckily, most hairball problems are minor and can be resolved with hairball remedies like gels or treats. More serious problems might require a temporary diet change like a cat food brand specifically designed for fighting hairballs.

Hairball control cat food isn’t dangerous for your cat but the high fiber content can have some unpleasant side effects if used over a long time. Here are the five most common problems associated with hairball cat food:


The 5 Side Effects of Hairball Cat Food

1. Cystitis

The high fiber content in hairball cat food has its downsides. One of them is the increased risk of cystitis or bladder inflammation. Your cat needs a lot of fluids to process and expel fiber and increasing the amount of fiber you feed them means increasing their water intake too. This isn’t always the easiest thing to accomplish—especially with stubborn felines.

Cystitis is painful and can be life-threatening if it prevents your cat from urinating at all. While this condition can’t be cured—and sometimes comes back—it is possible to treat and prevent it with help from your veterinarian. The symptoms include:

  • Behavioral changes
  • Bloody urine
  • Excessive or trouble urinating
  • Over-grooming around the genitals
cat licking itself
Image Credit: Kittisak Chysree, Shutterstock

2. Dehydration

One of the biggest problems when it comes to hairball cat food is the amount of water your cat needs to process the fiber content. A lot of cats don’t drink much water to start with. It can be a challenge to convince them to drink when they don’t want to, even if they have free access to clean water.

With the water they do drink reserved for processing the fiber needed to help their hairball issue, there isn’t a lot left for your cat’s other systems. Including their digestive system.

Severe dehydration can interfere with your cat’s organs, ability to control their body temperature, and neurological problems. Depending on the severity of your cat’s dehydration, you may also require a trip to the vet to ensure your cat receives proper treatment.

3. Diarrhea or Constipation

Some cats might be fine with the increased fiber content in hairball cat food but you should keep an eye on them just in case. Diarrhea and constipation can be caused by the fiber source in hairball formulas, especially if your cat normally struggles to digest the ingredients used in the recipe.

Hairball cat food can also cause issues if you introduce it to your cat’s diet too suddenly. Since it takes the place of your cat’s regular cat food while you’re treating their hairball problem, you need to introduce it slowly.

Similar to how you introduce a new flavor or brand of cat food, slowly increase the amount of hairball cat food you mix with your current formula. You’ll have to do the same process to return to your cat’s previous food once the treatment is complete.

old cat inside a litter box
Image Credit: Danielle Masucci, Shutterstock

4. Gastrointestinal Discomfort

Hairball cat food can be difficult to digest due to the high fiber content and the other vitamins and minerals used in the recipe. A lot of manufacturers of hairball cat food will use fiber sourced from plants to increase the effectiveness of the formula. While this works to boost the fiber content—and help remove hairballs from your cat’s system—it can be difficult for a lot of cats to digest.

The risk of dehydration can interfere here too. If your cat’s gastrointestinal tract has less water to use to work properly, it can increase the risk of infections and other GI issues.

5. Too Much Fiber

Fiber is an important addition to any diet but you have to keep in mind that too much of a good thing can cause problems too. While the high fiber content in hairball cat food helps ingested hair to pass through your cat’s GI tract, it can have a detrimental effect on their digestive system.

Along with gastrointestinal problems, too much fiber can also affect your cat’s overall health. It can affect their urinary tract health, bowel movements, and hydration.

The fiber content can also be dangerous for cats with other health problems regarding their kidneys or urinary tract. If the water these organs need to function correctly is used to process the extra fiber, your cat’s other health issues will worsen.

Cat eating pet food in a heart shaped bowl
Image Credit: Sharaf Maksumov, Shutterstock


What Causes Hairballs?

For animals who spend 30–50% of their day grooming themselves, hairballs are inevitable. As your cat grooms themselves, they ingest some of the loose and dead hair they remove from their coat. Unfortunately, the keratin protein that makes up hair—for both us and cats—isn’t digestible.

Normally, the hair passes through your cat’s system and is excreted in their poop. However, it can also get left behind in your cat’s digestive system. The more your cat grooms themselves, the more hair gets added to the clump in their stomach. It’s this wad of hair that your cat will throw up.

Hairballs are generally more common in long-haired cat breeds but they can affect all cats with hair, particularly as they age and become better at grooming themselves. Excessive grooming can also lead to more hairballs, which can be a result of an underlying health issue that needs to be treated.

cat sitting near hairball ant grooming brush
Image Credit: RJ22, Shutterstock

Signs of Hairballs in Cats

While they’re not pleasant for us or the cats who cough them up, hairballs usually pass through your cat’s system without causing a problem. There are occasions when they pose a more serious threat to your cat’s health.

A blockage caused by a hairball trapped in your cat’s digestive system, for example, can be life-threatening and require surgery to remove. Paying attention to the symptoms your cat shows can help you prevent the problem from becoming fatal:

  • Constipation
  • Diarrhea
  • Gagging or retching
  • Lethargy
  • Loss of appetite
  • Vomiting

Keep in mind that some of these symptoms can be a sign of other health issues too. If your cat is grooming themselves excessively—and making their hairball problem worse—it could be due to another health problem.

You should contact your veterinarian to properly diagnose the issue. To treat your cat’s hairballs, you’ll need to treat the underlying health issue too.

divider-catAlternative Remedies for Hairballs

Cat food formulas designed specifically for tackling hairballs aren’t the only solution to your cat’s hairballs. Sometimes, the cat food itself can even be unhealthy for your cat if you use it for too long.

Here are a few other remedies for hairballs that you can try instead:

Hairball Gels and Treats

If your cat’s hairball problem is a minor one, you might be able to tackle it with gels and treats that are formulated to control hairballs. These treats aren’t designed to be a major part of your cat’s diet and should be used alongside an already balanced meal plan.

They can, however, help hairballs pass harmlessly through your cat’s digestive system. While the hair won’t be digested, it won’t cause an obstruction or get coughed up by your cat either.

Regular Grooming

Grooming your cat helps to strengthen the bond between you and also helps you reduce hairballs. As you groom your cat, the brush will collect the dead and loose hair. By removing the hair before your cat can groom themselves, you’ll be reducing the amount of fur they ingest. In turn, this means less hair gets left behind in their digestive system and is less likely to end up as a hairball.

a person brushing the hair of a british shorthair cat
Image By: marketlan, Shutterstock



Hairball cat food is one of the ways many cat owners tackle their feline’s hairball problems. It is a high-fiber diet formulated to help indigestible hair pass through a cat’s digestive system. While it has its positives when it comes to preventing more serious issues related to hairballs and is generally harmless, hairball cat food also has a few side effects.

Gastrointestinal issues, dehydration, and cystitis are all possible side effects of hairball cat food and can be a result of long-term use of the formulas.

Featured Image Credit: Skrypnykov Dmytro, Shutterstock

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