Find BENADRYL® dosage information for adults, children, and toddlers and learn how much you and your family should take with our allergy medicine product-dosing guide. Benadryl (diphenhydramine) is an over-the-counter drug that’s used to treat allergies, cold symptoms, and other conditions. The drug comes as an oral tablet and other forms. It’s usually taken. Medscape - Hypersensitivity reactions, insomnia, antihistamine-specific dosing for Benadryl, Nytol (diphenhydramine), frequency-based adverse effects, comprehensive interactions, contraindications, pregnancy & lactation schedules, and cost information. Home › Health › Benadryl Dosage Calculator Benadryl Dosage Calculator Calculate the appropriate diphenhydramine (Benadryl®) dose based on body weight, age, and formulation. This tool supports liquid, chewable, tablet, and capsule forms for both children and adults. Giving your child Benadryl? Find the recommended amount of Benadryl to give your child based on age and weight using the St. Louis Children's Hospital Benadryl dosage chart. Detailed Diphenhydramine dosage information for adults and children. Includes dosages for Insomnia, Allergic Rhinitis, Allergic Reaction and more; plus renal, liver and dialysis adjustments. Find out how much Benadryl adults and children can safely take, plus essential safety tips and side effects to watch for in this medically-reviewed guide. Benadryl (diphenhydramine) is an over-the-counter medication that temporarily relieves allergy symptoms caused by the neurotransmitter histamine. Benadryl reduces symptoms such as runny nose, watery eyes, and itching in addition to causing drowsiness. The standard dosage of Benadryl is 25 to 50 mg (one to two tablets or capsules)every four to six hours with or without food. Children between. Benadryl (diphenhydramine) is an over-the-counter (OTC) antihistamine used to treat allergy symptoms, such as sneezing and runny nose. It’s safe for most adults and children ages 6 and older to take at recommended dosages. The typical adult Benadryl dosage is 1 to 2 tablets or capsules by mouth every 4 to 6 hours as needed. Adults ages 65 and older should contact a healthcare professional. Benadryl is a brand) name for diphenhydramine hydrochloride, a sedating antihistamine used to treat allergies, sleep problems, and motion sickness. The recommended dosage of Benadryl by condition is as follows.