Question: how much benadryl can i take for a severe allergic reaction?
Answer: First, an injection of epinephrine (EpiPen or EpiPen Jr) should be given to reduce the severity of the reaction. Second, taking liquid diphenhydramine (Benadryl) at a dose of 5 mg for every 10 lb of body weight, up to a maximum dose of 75 mg, also is recommended.