Overgrooming and hair loss in cats can be challenging to diagnose and treat| A Cat Clinic, Germantown, MDPosted February 19, 2019 by Dr. Dale Rubenstein.

Maybe you see your cat constantly licking her belly. Or maybe you’ve just noticed some scabbing along Tiger’s back when you pet him.  Perhaps your cat’s formerly thick fur coat is suddenly sparse and patchy.  Whatever the signs, over-grooming and hair loss in cats can be frustrating and difficult to deal with.

What does cause over-grooming and hair loss in cats?

There are many reasons for cat over-grooming, and figuring out which one is responsible for your cat’s problem can be challenging. About 80% are due to medical problems with the skin (dermatologic causes), and about 20% are due to anxiety or stress (neurologic causes). A small percentage may be caused by other metabolic problems or cancer. However, weight loss or other signs of a “sick” cat would usually be noticed before problems with the skin or hair coat.

Here are some of the most common causes of over-grooming and hair loss in cats.


Fleas are the #1 skin parasite in cats, but others include mites or rarely lice.  All can cause your cat to be itchy, groom himself frenetically and lead to hair loss, often with small bumps and scabs. Using a flea-comb on your cat usually reveals fleas or “flea dirt” (dried blood from when fleas have bitten the skin) when fleas are a problem.  However, some cats are such efficient self-groomers that although fleas are the cause, the evidence is erased faster than you can find it. A cat who is highly allergic may have very few fleas that are hard to spot, but still show an intense reaction by aggressively grooming his skin and fur.

For a cat that comes to see us for over-grooming without obvious evidence of other diseases, we typically start by treating for fleas. If fleas are the cause, the cat will show improvement quickly.  Treating the environment as well as the cat is critical for solving a flea problem. We recommend frequent vacuuming and covering favorite chairs with sheets, which can be easily washed.


This is actually a fungal infection, not a “worm”. It is contagious to people and dogs as well as other cats. Ringworm is more common in catteries where many cats are kept in close contact.  Kittens and certain purebred cats, such as Persians, are especially susceptible.

Ringworm seldom causes systemic illness. But it is very stubborn and takes diligent treatment of your cat as well as your home. It is slow-growing, so a minimum of 6 weeks of treatment is generally needed for control.


Cats, like people, can be allergic to anything in their environment and anything they eat. Humans are more likely to show respiratory signs (itchy eyes, congestion) or GI signs (bloating, intestinal discomfort). Allergies in cats, however, often manifest as skin disease.  In these cats, hair loss is a frequent complaint.

An extensive medical history, testing and treatment trials are often needed to determine the cause. Sometimes even with a diligent work-up we still don’t find a specific answer. But generally we can help your cat to feel more comfortable and lessen their over-grooming.

Allergic cats frequently have secondary problems, such as inflammation or infection. We need to treat these secondary problems, often before the allergy can be diagnosed. For example, a cat with allergies may also have ear mites.  Ear mites are easy to diagnose and treat.  However, if the the itchy ears continue even after the ear mites are treated properly, it may be due to allergies.


Since this is less common and is harder to diagnose, we focus on medical skin problems first. But if hair loss persists or you see your cat continue to over-groom after addressing the above possible causes, we turn our attention to possible behavioral causes.

We recommend a trial of anti-anxiety medication, as well as environmental enrichment. We need to address the difference between the home environment that we provide for our indoor cats and the free-ranging “great outdoors” that cats evolved to live in. You may think your cats have it easy, when they go back to sleep as you head off to work. But your indoor cats, while much safer, lead lives very different from the solitary hunters they were designed to be. And although housemate kitties may look like they’re great buddies, just watch one circle widely to avoid coming close to the other cat sometimes.  It’s clear that “friendship” is not always accurate.

For some suggestions on environmental enrichment, you may want to check out the Indoor Pet Initiative website.

So for over-grooming or hair loss in cats, start with good flea control measures.  We usually recommend Revolution, which treats both internal and external parasites (fleas and mites).  We also have a brand new product, Revolution Plus, which also treats ticks.

If the problems are not resolving, please schedule an appointment. Together, we can find out what might be bothering your cat and what we can do to help.