Benadryl is an anti-histamine = gets rid of allergy reactions and skin itches, i.e. insect bites, hives, etc. It can also be used as a mild sleep aid as it can and does make some folks sleepy. I take one 25-mg tablet at night every now and thento "take the edge off" so to speak so I can get to sleep and stay there for the night. Useful for dogs also when they get insect bites/stings especially on their faces/noses! One 25-mg tablet always help the doggies! Got that one from my Vet.