Atarax (Hydroxyzine) for Dogs and Cats

This is a medicine that was made for people as an antihistamine. Histamine is a chemical that is important to the body, primarily for controlling sleep in the brain, but it also is released by the body in response to allergens, causing many of the symptoms of allergies such as redness, inflammation, and itching.


General Flea Tipsheet

pictures of fleas

flea bites

Pet Questions

Pet Product Reviews


How does it work in pets?

Because it is an antihistamine, it is designed to stop histamine from working in the body. This keeps allergic reactions from happening, because it is not released in response to the allergens. Modern antihistamines are not able to go into the brain through the bloodstream, and thus they don't affect the useful histamine in the brain used for controlling sleep. It can penetrate somewhat, which results in drowsiness in some pets.

In a pet, it does not work as well or as consistently as in people. This is because histamine is not always responsible for the allergic reactions in pets - it's not as important to them, whereas with humans it's a key part of the immune response to allergies that results in inflammation. It generally is more effective in cats than in dogs, but because some dogs respond extremely well vets will often try it in both.

What is it used for in pets?

Allergic reactions and skin conditions are the primary ones. It can be used to reduce inflammation in response to a dog or a cat bitten by a snake, a cat or a dog stung by a bee, or certain bad reactions to other medicines. Sometimes it is also used as a tranquilizer or to treat nausea. It can also be used to treat used with cats to treat asthma or in dogs.

Does it have any side effects?

Yes. It can cause a pet to be drowsy or sleepy, and can cause a pet's mouth to get dry so that it drinks more water. It can react badly with other tranquilizers, so you should not use them at the same time. Also, a pregnant cat or dog should NEVER take Atarax. It causes birth defects if taken during pregnancy.

Sources and Useful Links:

Back to Pet Medications Page

Back to Flea Control Guide Main Page

Text copyright 2005-2006 and may not be reproduced without consent. This is not the official web page of any of the products listed on this site, this is a review page created by an individual. It is not by a vet, and is meant to be informative and not to substitute for a vet's advice - always consult a vet if you suspect a health problem.