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A member asked:

Will benadryl (diphenhydramine) have an effect on a methacholine challenge since its a anticholinergic drug?

A doctor has provided 1 answer
Dr. Gary Steven answered

Specializes in Pediatric Allergy and Asthma

Possibly : To get the best indication of bronchial hyper reactivity, you should not take any antihistamines for 3 to 7 days before the challenge. Unless, of course, the point is to see if Benadryl (diphenhydramine) will diminish the reactivity. That's why you need to discuss such questions with the physician who ordered the test.

Dr Ali agreed

Answered 5/12/2016

3k views

Thank

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