Age 12+ Take 1 to 2 tablets every 4 to 6 hours or as directed by a doctor. Ages 6-12 Take 1 tablet every 4 to 6 hours or as directed by a doctor. <span class=" fc-2nd">May 17, 2019 · </span> Benadryl is a brand-name, over-the-counter product thats typically used to relieve symptoms of hay fever ,...