Q: My cat was diagnosed with chronic allergic dermatitis. She is allergic to dust mites. Nothing cures it, but my vet has been giving her injections of a steroid called DepoMedrol every month. It relieves the symptoms but only for a few weeks. The cat’s chin and mouth area gets red, and she becomes very irritable and scratches at it. Is there anything I can do besides or instead of these injections?
A: Chronic allergic dermatitis, also called atopy (pronounced AT-a-pee), is a common problem in both dogs and cats, although it is probably under-diagnosed in cats. It is an inherited problem — one of your cat’s parents had allergies, and this was passed down to your cat.
The best treatment for allergic skin disease is to avoid the offending allergen. This, unfortunately, is not possible in the case of dust mites, as they are everywhere. The next best option is hyposensitization, a process that reduces sensitivity to allergens. In this scenario, a veterinary dermatologist prepares a vaccine consisting of the allergens that have been proven to trigger a reaction in your cat. You administer the vaccine to your cat according to a prescribed schedule, and your cat becomes less susceptible to allergy over time.
For people who choose not to visit a veterinary dermatologist and want to treat when a cat’s symptoms arise, there are several options. Steroids are often effective in controlling the itching and inflammation, but they have the potential for side effects, especially when injected. I prefer to prescribe steroids in pill form. The pills are given in higher doses at first, and then quickly tapered down to the lowest effective dose. Other possible treatments include oral antihistamines, omega-3 fatty acids and topical, anti-itch shampoos. In cases of seasonal allergy, the medication helps control the symptoms until the allergy season ends. However, if the allergen is something that persists in the environment throughout the year, like dust mites, your cat might have to be medicated continuously in order to keep her comfortable.