Hydroxyzine (whose brand names include Vistaril) and Benadryl (the brand name of diphenhydramine) are both first-generation antihistamines and share many similarities, including sedating side effects.

March 2, 2005 — The U.S. Food and Drug Administration (FDA) approved in December 2004 revisions to safety labeling to advise healthcare professionals of the following changes: use of hydroxyzine ...