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Allergy and Antihistamine Information Frequently Asked Antihistamine Questions Will taking antihistamines make me drowsy?
Will taking antihistamines make me drowsy?
The new non-drowsy, non-sedating antihistamines including Claratyne (Claritin), Zyrtec, Claramax (Clarinex) and Telfast (Allegra) are second generation antihistamines that rarely cause any drowsiness. If they do cause you to feel drowsy, do not drive or operate heavy machinery while affected.