Key takeaways: 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. Detailed Diphenhydramine dosage information for adults and children. Includes dosages for Insomnia, Allergic Rhinitis, Allergic Reaction and more; plus renal, liver and dialysis adjustments. Benadryl (diphenhydramine) is a brand-name drug used for allergies, allergic reactions, and itching. Benadryl comes in several forms that are available over the counter. The dosage can vary. Add 10 mL of 50 mg/mL diphenhydramine to 40 mL of NS Sedation is dose related and is similar to what would be expected for IM doses Relative contraindications are the same for IM diphenhydramine administration Pediatric Dosing Allergic reaction Oral/IM/IV: 5mg/kg/day divided q6-8h (1.25-1.67mg/kg/dose) Alternate PO dosing 2-6 yo: 6.25mg q4-6h Diphenhydramine (also known as Benadryl®) is a medicine used to treat allergic reactions, hives and allergies that affect the nose (called nasal allergies). It is an over-the-counter medicine, meaning that you can get it without a doctor's prescription. There are other medicines like diphenhydramine that might be safer for young children. Get the facts on Benadryl’s dosages. You can also learn how to take the drug, which forms it comes in, and more. 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. 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. 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.