Alopecia in Cats: What to Know

Alopecia is a common skin disorder in cats. It can affect cats of all ages, breeds, and genders, and the condition can be either gradual or acute.

What is Alopecia?

Alopecia typically refers to deficiencies in a cat’s coat or a failure to grow hair at all. Alopecia in cats causes the animal to have partial or complete hair loss, and can be symmetrical or varied—depending on the cause. It can affect a cat’s skin, endocrine system, lymphatic system, and immune system, in addition to his coat.

Feline symmetrical alopecia is one form of hair loss in cats; it’s defined by hair loss forming in a symmetrical pattern (on both sides of the body) without any distinct changes to the skin. With symmetrical alopecia, the most commonly affected areas are a cat’s trunk and thighs.

Typically, alopecia is a sign of an underlying medical issue which must be identified for the condition to be successfully treated. While it’s normal for cats to shed and sometimes have patchy coats in between seasons—like when a cat is shedding his winter coat—alopecia is usually a very distinctive type of hair loss.

What Causes Alopecia in Cats?

When it comes to alopecia in cats, causes can vary. Alopecia and hair loss can be congenital, which means a cat is born with the condition, or acquired. It occurs when the growth of hair follicles becomes disrupted.

Inflammation in cats can cause damage to the hair follicle and result in hair loss. Certain infections and diseases can cause hair loss in a more widespread area of the body; these may impede hair growth or completely destroy the hair follicle or shaft, causing the hair to fall out. If alopecia occurs due to an inflammatory cause, it may also lead to discomfort, pain, or itchiness in cats.

Congenital Hair Loss

Not every type of congenital hair loss is hereditary, although it usually does have some sort of genetic basis. Congenital alopecia happens when there is a lack of normal hair follicles. The disorder can either be noticeable at the time of birth, or symptoms can be suppressed until the cat is at a certain age when hair loss begins to occur. Congenital hair loss can either be symmetrical or localized to one area.


Hair loss can happen in association with atopic dermatitis, which is a chronic, inflammatory skin disease caused by allergies. Cats allergies are quite common. The common sources of cat allergens include insect bites, grasses and pollens, dust mites, mold spores, cleaning products, food, perfumes, certain fabrics and materials, and prescription medications. Allergy symptoms often include cat coughing or sneezing, feline vomiting, rashes, and itching. Cats will often scratch or chew at their skin to relieve their discomfort, damaging their coats even further.

Bacterial & Fungal Infections

Fungal and bacterial infections can cause partial to complete alopecia in cats. Ringworm is a very common fungal infection, and it appears as hair loss in circular patterns, and sometimes lesions, inflammation, redness, and crusting. Some fungal infections will clear up on their own, while others will require more proactive treatments, like antifungal medications, shampoos, or ointments. If the cause of alopecia is due to a fungal infection, cat owners should take special precaution as some infections can be zoonotic, which means it can be contracted and spread from one species of animal to another.

Bacterial infections, on the other hand, usually need to be treated with antibiotics prescribed by a vet. One common bacterial infection in cats is caused by Staphylococcal (staph), this usually presents as redness and crusting, along with hair loss.

Hormonal Imbalances

Alopecia in cats can sometimes be caused by hormonal imbalances or endocrine disorders. There are specific hormones that are responsible for hair growth in cats, so an excess or deficiency in any of these can lead to hair loss or slow hair follicle growth. Cats who are pregnant or lactating can experience hormonal changes, and may lose some hair as a result; other causes of alopecia due to hormones might be hypothyroidism or hyperthyroidism, Addison’s disease, Cushing’s disease, and increased levels of steroids. Hormone-related alopecia is usually noninflammatory, and any itching is typically relating to a secondary skin infection or other source.


Mange is a common reason for hair loss in cats. It is caused by an overpopulation of Demodex mites, which cannot be seen by the naked eye. When these mites start to inhabit a cat’s hair follicle, it can cause skin conditions like lesions, hair loss, and crusting of the skin, especially if left untreated. Mange is classified as an inflammatory disease, but symptoms (other than hair loss) and the severity of symptoms, can depend on the type of mite the cat has.


If a cat is dealing with pain, like feline arthritis, he may lick himself in an attempt to relieve the pain. When alopecia occurs for this reason, hair loss will stop when the pain stops.

Stress & Nervous Disorders

Compulsive behaviors, such as excessive licking, chewing, and grooming, have been known to appear in cats with anxiety, depression, or other psychological disorders. When they’re in duress or feeling nervous, cats turn to these behaviors as a way to soothe, however, it can lead to localized hair loss in areas where they’re searching for relief. This is often referred to as psychogenic alopecia.

Sometimes alopecia can also occur on its own, with no particular cause at all.

Signs & Symptoms of Alopecia in Cats

Alopecia can present itself as a large variety of symptoms, but it is usually very distinct. It’s usually characterized by hair thinning or balding; other symptoms are dependent on the underlying cause (such as infection or disease) of the hair loss.

Hair loss can occur gradually over time, or be acute, with hair loss and other symptoms appearing suddenly. Alopecia can be localized, appearing in only one area, or it can spread to multiple areas of the body as the condition progresses. The hair loss may also be symmetrical, showing up on both sides of the body, or isolated and sporadic.

Occasionally, alopecia in cats causes inflammatory reactions, where the hair loss is accompanied by redness, irritation, and crusting of the skin. Other times, the skin around the affected area seems normal (or inflammatory), and the cat will show no reaction to the disorder—this is typical with congenital alopecia.

Alopecia is often associated with clinical symptoms beyond hair loss. Behavioral signs of alopecia are itching, scratching, chewing, and licking, as cats try to cope with the irritation. Depending on the cause of the hair loss, the skin affected by the alopecia will become irritated, discolored (either with red or gray-ish tones), and inflamed. If the situation is severe, the affected areas can develop sores or blisters.

Some causes of alopecia may lead to the development of secondary skin diseases, such as infection or fluid discharge. These can lead to foul odors, and crusty, thickened, or raised skin.

How is Alopecia Diagnosed?

If you think your cat may have alopecia, and it seems to have appeared suddenly, then take him to the vet immediately for an accurate diagnosis and treatment.

During the appointment, your vet will need information on your cat’s medical history. The appointment will also likely include a physical examination to determine the cause of the alopecia.

Your vet will probably ask you when the hair loss started, how it has progressed, and whether your cat has been itching and scratching excessively. You may also need to note whether you’ve seen any other symptoms that could be associated with an infection, such as lethargy or frequent urination.

The rest of the appointment will include a p