Why Does My Cat Have Hairballs? Causes and Fixes

Your cat has hairballs because grooming swallows loose hair, and hair is made of keratin that cannot be digested, so some of it collects in the stomach and comes back up. An occasional hairball is normal. Repeated unproductive retching, or vomiting plus a loss of appetite, can signal a blockage and needs a vet.

Hairballs are one of the most common things cat owners ask about, and most of the time they are a harmless nuisance rather than a disease. Still, frequent hairballs are not purely cosmetic, and they can overlap with the causes covered in our guide to why your cat is throwing up.

Why do cats get hairballs in the first place?

Cats are meticulous self-groomers. The surface of a cat's tongue is covered in tiny backward-facing barbs, called papillae, that act like a comb and catch loose hair as the cat licks. Those barbs point toward the throat, so any hair they snag can only go one way, which is down and swallowed. A cat that grooms normally ingests a surprising amount of its own coat every day.

Most of that swallowed hair passes straight through the digestive tract and leaves in the stool. The problem is that hair is built almost entirely from keratin, a tough structural protein that the acids and enzymes in a cat's stomach cannot break down. As VCA Animal Hospitals explains, this indigestible hair normally moves through the intestines and exits in the feces, but when too much collects in the stomach it clumps into a wad known medically as a trichobezoar. When that wad grows large enough to irritate the stomach, the cat brings it back up.

A few cats are simply more prone to this than others. Kittens rarely produce hairballs because they have not yet perfected the vigorous grooming that adults do, while the habit becomes more established with age. Cats that shed heavily, cats that groom a housemate as well as themselves, and cats in warm shedding months all swallow more hair per day. None of that is abnormal on its own; it just raises the odds that some of the hair will pool into a ball rather than clear the gut.

Despite the name, a disgorged hairball is rarely a neat ball. According to the Cornell Feline Health Center, hairballs are usually slender and cylindrical, shaped more like a cigar than a marble, because they take the narrow form of the esophagus they travel up through.

How often is a hairball normal, and how often is too often?

An occasional hairball is part of normal cat life. Cornell notes that it is not uncommon for a cat to bring up a hairball once every week or two, and aside from the mess this is generally nothing to worry about. Long-haired breeds such as Persians and Maine Coons tend to produce them more often simply because they swallow more hair, and shedding season can bump the frequency up for any cat.

What is not normal is a cat that produces hairballs very frequently, such as several times a week or more, or a cat whose hairballs come with other changes like a dull coat, weight loss, reduced appetite, diarrhea, or low energy. PetMD points out that frequent hairballs usually trace back to an underlying issue, most often gastrointestinal disease or a skin condition that drives excessive self-grooming, so home remedies alone will not fix them. If the frequency is climbing, that is a reason to book a vet visit rather than reach for another tube of hairball gel.

When is a hairball actually dangerous?

The rare but serious risk is a blockage. A hairball can grow too large to pass through the narrow openings that lead from the esophagus into the stomach or from the stomach into the intestines. Cornell warns that a hairball which slips into the small intestine and lodges there is uncommon, but very serious when it happens, and may require surgery to remove because it can otherwise be fatal.

The classic warning sign is a cat that keeps hunching and retching or gagging over and over without ever producing a hairball. That repeated, unproductive heaving is different from the usual one-and-done episode, and it can mean the hair is stuck. Cornell lists ongoing vomiting, gagging, retching, or hacking without producing a hairball, along with a loss of appetite, lethargy, constipation, or diarrhea, as signs that warrant a call to the veterinarian. If your cat retches repeatedly and nothing comes up, treat it as a vet problem, not a hairball to wait out.

Two more red flags overlap with hairball season. A cat that stops eating for more than 24 hours is at risk of a dangerous liver condition called hepatic lipidosis and should be seen, and any cat that seems weak, painful in the belly, or is straining without passing stool needs prompt care. It also helps to remember that not every hacking, coughing cat has a hairball at all. A dry, repeated cough with no hairball can be feline asthma or another airway problem rather than a digestive one, and that is worth mentioning to your vet because the treatment is completely different. When in doubt, our overview of the broader signs your cat is sick can help you decide whether a symptom is a nuisance or an emergency.

How can I reduce my cat's hairballs?

The single most effective thing you can do is remove loose hair before your cat swallows it. Regular brushing catches shed hair on the comb instead of the tongue. International Cat Care recommends grooming long-haired cats at least daily and short-haired cats at least weekly, always for only as long as the cat stays comfortable. Cornell makes the same point, advising owners to accustom a cat to daily brushing and combing, and to consider a professional groom once or twice a year for long-haired cats that will not tolerate it. If your cat resents a comb, our guide to bathing a cat covers gentler ways to manage a heavy coat.

Diet and hydration matter too. VCA notes that a diet lacking in fiber can contribute to hairball formation, because fiber helps sweep ingested hair through the digestive tract before it clumps. Keeping your cat well hydrated, including offering wet food, supports that same movement through the gut. Getting portions and food type right is worth reviewing in our guide to how much to feed a cat. The table below lays out the main levers you can pull.

Do hairball diets and remedies actually work?

For a cat with the occasional hairball, they can help. Hairball-control diets typically add insoluble fiber to help push swallowed hair through the intestines, and lubricating gels coat the hair so it slides through more easily. PetMD describes both approaches as reasonable for infrequent hairballs, with a high-fiber diet helping some cats and lubricant gels easing passage in others.

The important caveat is that these are management tools, not cures for an underlying problem. PetMD is clear that home treatment is not appropriate for a cat that has frequent hairballs, because an underlying health issue is usually to blame, and if that issue is not treated the cat will not improve no matter how much gel or special food you use. Always run any remedy past your veterinarian before starting it, and never guess at a dose. If the products are not keeping up, that is a signal to investigate, not to double the dose.

When do hairballs point to a bigger problem?

Frequent hairballs are often a symptom rather than the disease. VCA notes that trichobezoars are more common in cats with underlying gastrointestinal disease, because conditions that alter gut motility slow the movement of hair through the tract. Cats with allergies or other skin disease are also more prone to hairballs, since itchy or irritated skin makes them lick and over-groom, swallowing far more hair than usual.

Inflammatory bowel disease and food allergies are two common hidden drivers, because the inflammation they cause interferes with the gut's normal ability to handle swallowed hair. That is why a cat whose hairballs are increasing, or whose coat, appetite, weight, or litter-box habits are changing at the same time, deserves a workup rather than another remedy. A vomiting cat in general is worth a look; the Cornell Feline Health Center lists a long list of causes for feline vomiting beyond hairballs, from dietary issues and parasites to kidney and thyroid disease.

Excessive grooming can also start with nails and skin discomfort. If your cat seems to be over-grooming a particular spot, keeping claws in good shape with our guide to trimming cat nails is one small piece of good coat care, though persistent over-grooming still needs a vet to rule out pain, parasites, or stress.

When should I call the vet about hairballs?

Call your veterinarian if your cat is retching, gagging, or hacking repeatedly without bringing anything up, if hairballs suddenly become frequent, or if they come with a loss of appetite, weight loss, low energy, constipation, or diarrhea. These are the patterns Cornell flags as reasons to seek care rather than wait.

Treat it as an emergency, and go in without delay, if your cat is trying to vomit repeatedly and producing nothing, has a swollen or painful belly, has not eaten for more than 24 hours, is weak or collapsed, or is straining to defecate without success. A hairball lodged in the intestine is a surgical problem, and time matters. This is educational guidance, not a diagnosis, and only a vet who can examine your cat can tell a routine hairball from a blockage or an underlying disease.

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