Feline Miliary Dermatitis in Cats

Cats that develop feline miliary dermatitis display:

• Tiny, red crusty bumps on the skin (near the head and neck, and running down the back)
• Hair loss
• Intense itching and scratching
• Hair pulling
• Thickened skin that is darker than surrounding skin
• Grazed areas on the skin resulting from constant scratching

When a food allergy causes feline miliary dermatitis, the cat develops sores and scabs around its head and tail. Some circular sores can be found around the shoulders.

Cats can develop this skin condition from one of many causes, or a combination of several:

• Bacterial infections
• Flea bite hypersensitivity (most common cause)
• Cheyletiellosis mite
• Hormone/endocrine disorder
• Allergies (food, inhalant, or food intolerance issues)
• Drug hypersensitivity
• Poor diet
• Mites
• Ringworm
• Immune-mediated diseases (immune disorders)
• Contact allergies (rare)

In warm-climate areas or flea-infested areas, this skin condition can develop more frequently in cats. Cold-winter regions may see this condition develop much more often in the summer months.

The vet will rely mainly on the cat’s medical history and the clinical signs of the condition to make a diagnosis. If they know, for instance, that the cat has experienced food intolerance or food allergies, they are more likely to tell the cat’s owner that the cat has developed feline miliary dermatitis.  

It’s not easy to spot fleas on a cat, but if the vet sees flea dirt or feces on the cat, they are also likely to provide this diagnosis. The cause may be determined as a flea allergy, but if it doesn’t respond to a flea treatment, the vet will run additional tests to narrow down the diagnosis:

• Serum IgE allergy testing
• Skin scraping
• Fur samples
• Hypoallergenic food trial
• Fecal examination to look for intestinal parasites
• Biochemical profile
• Biopsies
• Referral to a veterinary dermatologist

Veterinarians take into account the locations of the rashes and lesions in making their diagnosis. They will also measure the size of the lesions and determine what kind they are.

Treatment is straightforward: Remove the irritants and make the cat more comfortable until the lesions heal.

Cat owners need to remove fleas from the cat’s home environment, which may help relieve many of its symptoms. If the fleas return, the allergy symptoms and rashes will return. Because cats groom themselves daily, it’s rare to find live fleas on their bodies.

If the cause of the cat’s skin condition is a food allergy or intolerance, the pet owner will need to switch the cat to a different food. It is vital that, once a food allergy has been diagnosed, the cat does not eat the allergy-causing food. If the cat has been allowed to roam outdoors, it will have to stay indoors permanently to reduce the risk of eating an offending food or hunting and eating prey that could cause a relapse.

The cat owner will need to give the cat one of several medications:

• Antihistamines
• Corticosteroids
• Fatty acid supplements (skin oil replacements)
• Antibiotics
• Topical ointments
• Special shampoo to stop inflammation and itching

For intestinal parasites, the cat will have to take medication that helps to eliminate the parasites.

Allergy shots for cats are controversial—they are used only for cats who are severely affected

The prognosis for cats diagnosed with miliary dermatitis are excellent. Once the offending substance has been eliminated from the cat’s environment or food, the cat will recover. Its skin will heal and fur will grow back.

The pet owner will have to be vigilant in keeping fleas from returning to the home if the cat’s condition is flea allergy-related. The new food given to the cat will be a permanent part of its diet. Since many causes of miliary dermatitis are allergy-related, the cat may need occasional treatments with corticosteroids to keep flare-ups from becoming severe. 

As the cat gets older, its allergies may get worse. If it has been diagnosed with more than one allergy, its recovery may not be total, meaning it needs to continue with treatment to keep skin reactions and symptoms under control.