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A member asked:

If i take benadryl (diphenhydramine) a day after i got the tb test will it interfere with it? (make it positive/negative)

5 doctors weighed in across 2 answers

No effect: The reactivity of the tuberculin test relies on immune factors not allergic responses. Benedryl will have no effect on that process.

Dr Fowler and 2 doctors agreed

Answered 4/7/2020

4.9k views

Thank
Dr. Troy Ross answered

Specializes in Occupational Medicine

No problem: The TB test checks for an antibody response to proteins from the bacteria. Medications won't interfere with that.

Answered 7/24/2019

4.9k views

Thank

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