Question: how many milligrams of diphenhydramine can i take?
Answer: For adults and children over 12 years of age, the maximum is 300 mg each day. For children ages 6 to 12 years, the maximum is 150 mg each day. For adults or children, Benadryl products such as the cream, gel, and spray shouldn't be applied to the skin more than 4 times per day.