Question: are cetirizine hydrochloride and cetirizine dihydrochloride the same?
Answer: Two popular FDA-approved medications are Xyzal (levocetirizine dihydrochloride) and Zyrtec (cetirizine hydrochloride). Both medications are antihistamines, also called H1 blockers. They block the action of histamine, thereby relieving allergy symptoms.