Causes of Cat Hair Loss and How to Manage Them

Skin & CoatSymptomsMeongsiljang Veterinary Advisory Board

There are many reasons why cats lose their fur, ranging from stress-induced overgrooming to skin infections and hormonal imbalances. Here’s a guide to distinguishing symptoms by cause and practical steps you can take at home.

What to Check First If Your Cat Is Losing Hair

The most common cause of hair loss in cats is self-induced alopecia due to excessive grooming. However, most cases of self-induced alopecia have underlying medical causes such as allergies, parasites, or infections. "Psychogenic alopecia" is a diagnosis of exclusion that can only be made after ruling out all these medical causes. Since the appropriate response varies significantly depending on the cause, it is important to carefully observe the pattern of hair loss and any accompanying symptoms. I will now outline how to differentiate the causes, when to visit the clinic, and how to manage the condition at home.

Three Hair Loss Patterns – Identify the Type First

Feline hair loss can generally be categorized into three main patterns.

Self-traumatic alopecia: This type of hair loss occurs when a cat excessively licks or bites its own fur. It most commonly appears on the chest, abdomen, groin, flanks, inner and rear thighs, and front legs.

Localized alopecia: This pattern involves circular patches of hair loss confined to specific areas. Dermatophytosis (a fungal infection) is a typical cause.

Symmetrical alopecia: This pattern features hair loss that occurs symmetrically on both sides of the body. In cats, this is most often caused by self-traumatic over-grooming due to itching (such as from allergies), while hormonal imbalances are relatively rare.

Identifying the pattern is a great help in narrowing down the underlying cause.

Suspect Hair Loss If You Notice These Symptoms

If you notice any of the following symptoms, it’s important to identify the underlying cause.

Localized hair loss: Hair falls out in concentrated patches, particularly on the belly, inner legs, or near the tail.

Skin redness and scaling: The skin in the bald areas appears red or develops white, flaky scales.

Excessive grooming: Your pet licks its body much more frequently and for longer periods than usual. In severe cases, this can lead to abrasions or ulcers.

Scaling, crusting, or redness in bald areas: If hair loss is accompanied by scaling, crusts, or redness, ringworm (dermatophytosis) should be considered in the differential diagnosis. Ringworm can appear on various parts of the body, including the muzzle, limbs, and ear flaps.

Increased hairball frequency: Excessive grooming leads to swallowing more hair, which can cause digestive issues.

A cat lying on its back with its belly exposed

When to Visit the Vet Immediately

Please visit a veterinary clinic as soon as possible if any of the following apply: • A large area of skin is red, swollen, or oozing fluid. • Crusts or pustules (small bumps filled with pus) are visible in the hairless areas. • Hair loss is accompanied by rapid weight loss or decreased appetite. • Hair loss has been spreading rapidly for more than two weeks. In particular, because dermatophytosis (a fungal infection) can be transmitted to humans, prompt diagnosis is essential.

Cause ① Stress-Induced Overgrooming

While psychogenic overgrooming is an important consideration in cases of self-induced alopecia in cats, medical causes such as allergies, infections, and parasites are actually more common. When stressed, cats may lick their bodies repetitively, and if this behavior becomes compulsive, it can lead to hair loss and exposed skin. Common stressors include moving, the addition of new family members (human or animal), changes in litter box environment, and noise. According to veterinary dermatology textbooks, psychogenic alopecia is a diagnosis of exclusion, meaning it is diagnosed only after all other skin diseases have been ruled out. Even if the cause appears to be stress, underlying allergies or infections may be present, so it is essential to have your cat examined by a veterinarian.

Cause ② Skin Infections – Fungi, Parasites, and Fleas

Skin infections are also a major cause of hair loss in cats.

Dermatophytosis (fungal infection): This condition is characterized by hair loss accompanied by scaling, crusting, and redness. Lesions can appear in various forms and locations, commonly affecting the muzzle, limbs, ear flaps, areas around the eyes, and the tail. It is relatively common in young cats and can be transmitted to humans, making prompt treatment essential.

Demodicosis: Although rare in cats, an overgrowth of Demodex mites can lead to hair loss, particularly in cats with compromised immune systems.

Flea allergy dermatitis: An allergic reaction to flea saliva causes intense itching and hair loss, typically around the tail base and on the inner thighs.

Cause ③ Allergies and Hormonal Imbalances

Allergies and hormonal imbalances can also cause hair loss.

Food allergies: Reactions to specific proteins can lead to itchy skin and hair loss. Diagnosis often involves a veterinarian-supervised elimination diet using a novel protein source for a set period.

Atopic dermatitis: Chronic itching and hair loss occur in response to environmental allergens such as house dust mites and pollen.

Hyperthyroidism: This condition is considered one of the causes of self-inflicted hair loss in senior cats. If weight loss and increased appetite are present, blood tests (including blood chemistry and hormone panels) are recommended.

Causes Often Overlap

Feline hair loss often stems from multiple overlapping causes. For example, allergies can cause itching, leading to overgrooming, which may then result in secondary bacterial infections. This is why veterinarians perform skin tests—such as fungal cultures and skin scrapings—in a step-by-step manner. Since it’s difficult for pet owners to pinpoint the exact cause on their own, please seek veterinary care if hair loss persists for more than two weeks.

At-Home Hair Loss Management Tips

Along with targeted treatment, there are several steps you can take at home to support your cat’s recovery.

Stress management: Provide plenty of cat trees for climbing and cozy hiding spots. Pheromone diffusers can also help ease anxiety during environmental changes.

Regular brushing: Brushing two to three times a week removes dead hair and gives you a chance to check your cat’s skin condition.

Flea prevention: Consistent monthly use of flea preventatives helps avoid flea allergy dermatitis.

Balanced diet: High-quality food rich in protein and omega-3 fatty acids supports healthy skin and coat.

Reviewed by a veterinarian

Dr. Tony — Punnawat Phongkittirak

Veterinarian

A veterinarian who majored in veterinary medicine at Khon Kaen University, Thailand, and completed the IVSA program at North Carolina State University in the United States. Drawing on clinical experience at animal hospitals, he works in the pet healthcare field and is dedicated to building a digital care environment that connects pet parents with veterinarians.

Frequently Asked Questions

My cat is only losing hair on its belly. Why is that happening?

Hair loss on the belly is a common pattern in self-induced alopecia caused by excessive licking. However, underlying causes such as allergic itching are often present, and if the hair loss is confined to the lower abdomen and groin, it may be associated with lower urinary tract diseases like cystitis. Psychogenic (stress-related) overgrooming is a diagnosis of exclusion, meaning it can only be diagnosed after all medical causes have been ruled out. Therefore, it is best to have a veterinarian determine the cause rather than relying on self-diagnosis.

Can cat hair loss be transmitted to humans?

If the cause is dermatophytosis (a fungal infection), it can be transmitted to humans. If you notice circular hair loss and scaling, seek veterinary care promptly, and be sure to wash your hands thoroughly after any contact until the infection has been ruled out.

What tests are performed at the clinic for hair loss?

First, we’ll perform a skin scraping (scraping the skin and examining it under a microscope) and a fungal culture test. Depending on the case, we may also conduct additional tests such as blood work, allergy testing, or a skin biopsy.

Are there any supplements that help with hair loss in cats?

Omega-3 fatty acids can help support skin barrier function and reduce inflammation, making them a useful supplement. However, hair loss rarely resolves with supplements alone, so treating the underlying cause is essential. Please consult your veterinarian before starting any new supplement.

Is the excessive shedding during seasonal changes considered hair loss?

Shedding during spring and fall is a normal occurrence. However, if certain areas appear noticeably thin or the skin is visible, this is not normal shedding, and a veterinary examination is necessary.

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References

[1] BSAVA Manual of Canine and Feline Dermatology, 4th Edition, Chapter: Non-pruritic symmetrical alopecia

[2] Peter Hill, 100 Top Consultations in Small Animal General Practice, Ch.33: The dog that is losing hair

[3] Miller WH, Griffin CE, Campbell KL. Muller and Kirk's Small Animal Dermatology, 7th Ed. Elsevier, 2013