Arguably the easiest way to dose Benadryl is by weight. The following chart describes the maximum Benadryl dose in milligrams (mg) or milliliters (mL) based on a person's weight in pounds (lbs).

Consult your dog’s veterinarian for the most accurate dose based on weight. You can give your dog 1 mg of Benadryl per pound, so if it weighs 10 pounds, you can give it a 10 mg dose up to three ...