Antihistamine Treatment of Dog Allergies: H1 and H2 Blockers

Antihistamines are medications that are used for dog allergies treatment. Antihistamines are effective in treating allergies in up to 30% of dogs when used alone. When antihistamines are combined with other control measures, such as avoidance of the allergen and fatty acid supplementation, the success rate increases. 

Most Common Antihistamines Are H1 Blockers

When histamine affects a cell via a histamine receptor on the cell wall, it results in allergy symptoms. Antihistamines block the histamine receptors, preventing allergic reactions.

Common Side Effects of Dog Allergy Treatments

Every animal will respond differently to antihistamines, so several may have to be tried to find the most effective one for your pet. Each medication has a different dosage and side effect profile. Common side effects include sedation, dry mouth, hyperactivity and lack of appetite. When the most effective dosage is obtained side effects should be minimal with optimal relief of symptoms.

Common Antihistamines to Treat Allergies

H2 blockers (such as Claritin® and Hismanal®) have been very effective for use in human allergies, but they have not been found to be effective in the treatment of canine allergies and are not recommended for use in pets. The most common antihistamines used in pets are Bendaryl®, Atarax®, Tavist® and Chlor-Trimeton®.