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A 35-year-old member asked:

How many days does it take for allegra (fexofenadine) to work?

2 doctor answers4 doctors weighed in
Dr. Andrew Murphy
Allergy and Immunology 30 years experience
Hours: Allegra (fexofenadine) and most oral antihistamines will start to work within an hour or so. It does not take days for these medications to work.
Dr. Heidi Fowler
Psychiatry 26 years experience
Allegra: Allegra can start working within a hour.

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Last updated Jun 5, 2021

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