Updated On September 23rd, 2025
Pet's info: Cat | Domestic Shorthair | Male | neutered | 9 lbs
My cat, Jacob, was recently diagnosed with allergic bronchitis and benadryl isn't effective in controlling his pollen allergies. What is the difference between benadryl, cyproheptadine, and hydroxyzine? They're all antihistamines. Is one more effective than the other or do they all work the same even though they are different chemicals?
1 Answer
Published on April 21st, 2018
Thanks for using Petco Pet Education Center, formerly Petcoach! Excellent question. They are all about the same though their efficacy is a bit different. This is because while they have the same mechanism of action, their bioavailability meaning how much is used by the body when taken is different. Benadryl appears to be the most effective out of the three in my experience and that is the one I would recommend though in theory they all should work. Good luck and have a great day!
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