My dog's itchy rash on stomach, legs, armpits. Benadryl not working?
The spots where the rashes are definitely fit with seasonal environmental allergies. They may not have been there before, but would not be due to the Benadryl. It's more likely that it's a progression of the allergies and a sign that the Benadryl is not working well. Dogs tend to not be helped by certain antihistamines, but may be helped better by others. Luckily there are a few alternatives that can be bought over the counter. I recommend calling you veterinarian and asking if they could suggest another antihistamine. As long as they have no other concerns with Riley, they should be happy to give you an alternative. If the second antihistamine doesn't work and you still notice the rash/itching, then he will likely need a recheck exam and stronger medication.
One thing you can do for the rash and itchy skin, is give a bath with cool water using an oatmeal or aloe shampoo. You can get these shampoos at the pet store.
I hope that helps and Riley gets better soon.
Updated on September 23rd, 2025