Not FDA approved for veterinary use but it is a common and accepted practice to use hydroxyzine in dogs. Other medications may be preferred in cats due to the side effects and lack of safe dosage information. Available by prescription. Histamine is released by body tissues during an allergic reaction. Symptoms include itching, sneezing, and swelling especially of the face.
Anaphylactic shock is a severe and possibly fatal allergic reaction.
One type of antihistamine may work better than another in some pets so trial periods of 1-2 weeks may be needed using different antihistamines to determine which works best at relieving the symptoms. Hydroxyzine also relaxes muscles, decreases nausea, opens airways, and decreases pain. Duration of treatment depends on the reason for treatment and response to treatment. Side Effects May see sedation. Less commonly seen are excitement, fine tremors, whole body tremors, or seizures.