Can Fleas Cause Scabs on a Cat's Back & Butt?

If I just don't think about it, it will stop itching right?
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You notice that instead of playing and pouncing, your little kitty’s attention now focuses on scratching, licking and biting his back and butt. You discover that his skin is a minefield of scabs. While large-mouthed fleas are not biting holes in your cat, they are playing a role.

Flea Allergic Dermatitis

While the idea of fleas may make your skin crawl, the truth is, most cats only experience minor skin irritations to flea bites. Unfortunately, not all cats are this lucky. Your cat may suffer from flea allergic dermatitis. In this case, an allergy to the proteins in the flea saliva causes inflammation and irritation. Symptoms include chewing, biting, scratching, open sores, scabs and hair loss. For these cats, a large flea infestation is not necessary to bring about a reaction. A single bite from one flea can produce intense symptoms.

Diagnosing and Secondary Conditions

If you notice scabs on your cat, consult a veterinarian. Unfortunately, diagnosing flea allergic dermatitis can be difficult. Cats are very clean animals and groom often. A cat with intense itching from flea allergic dermatitis will do everything possible to remove traces of fleas and the fleas themselves. Because of this, a standard flea examination may not find any fleas. If fleas or flea dirt are not present, your vet may begin by ruling out other possible allergies first, such as food allergies. In addition, the scabs created by the scratching and biting may lead to hot spots or secondary skin conditions that require treatment.


If your cat suffers from flea allergic dermatitis, getting rid of the fleas is essential. Talk with your vet about the best possible flea treatment for your cat and make sure he receives it as recommended. Secondary skin infections may require treatment with antibiotics or antifungal medications. If the inflammation and itching are intense, your vet may recommend corticosteroids.


With a flea allergic dermatitis cat in your family, flea prevention is essential. In addition to treating your cat with regular flea treatments, you must address your home and yard as well. Wash your cat’s bedding in hot water and vacuum floors on a regular basis to remove flea eggs. Be sure to empty vacuum bags after every use. For a natural flea treatment for your carpets and furniture, mix together one part baking soda, one part cornstarch and two parts diatomaceous earth. Sprinkle the mixture on carpets and upholstery and let it sit overnight before vacuuming again. These substances dehydrate and kill fleas and larvae.

Always check with your veterinarian before changing your pet’s diet, medication, or physical activity routines. This information is not a substitute for a vet’s opinion.

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