Diphenhydramine (Benadryl) Dosage Table

Diphenhydramine (Benadryl, etc.) Dosage Table

Child's weight (pounds) 20-24 25-37 38-49 50-99 100+ lbs.
Liquid 12.5mg/5ml (tsp) ¾ 1 2 -- tsp
Liquid 12.5 mg/5 milliliters (ml) 4 5 7.5 10 -- ml
Chewable 12.5 mg -- 1 2 4 tablets
Tablets 25 mg -- ½ ½ 1 2 tablets
Capsules 25 mg -- -- -- 1 2 caps

Indications: Treatment of allergic reactions, nasal allergies, hives and itching.

Table Notes:

  • AGE LIMITS: For allergies, don't use under 1 year of age (Reason: it's a sedative). For colds, not recommended at any age (Reason: no proven benefits) and should be avoided if under 4 years old. Avoid multi-ingredient products in children under 6 years of age (Reason: FDA recommendations 10/2008).
  • DOSAGE: Determine by finding child's weight in the top row of the dosage table
  • MEASURING the DOSAGE: Syringes and droppers are more accurate than teaspoons. If possible, use the syringe or dropper that comes with the medication.  If not, medicine syringes are available at pharmacies. If you use a teaspoon, it should be a measuring spoon. Regular spoons are not reliable. Also, remember that 1 level teaspoon equals 5 ml and that ½ teaspoon equals 2.5 ml.
  • ADULT DOSAGE: 50 mg
  • FREQUENCY: Repeat every 6 hours as needed
  • CHILDREN’S BENADRYL FASTMELTS: Each fastmelt tablet contains the equivalent of 12.5 mg of Diphenhydramine HCL and dosed the same as chewable tablets.

Author and Senior Reviewer: Barton D. Schmitt, M.D.

Content Set: Pediatric HouseCalls Symptom Checker

Pediatric HouseCalls Symptom Checker

Is Your Child Sick?

Pediatric HouseCalls Symptom Checker is a parent guide for treating your child at home, calling your child's doctor or seeking immediate medical attention. Developed by Dr. Barton Schmitt, MD, FAAP, a board-certified pediatrician on staff at Children's Hospital Colorado. Dr. Schmitt has developed other health tools for parents, including the 3rd edition of Your Child’s Health (available in bookstores) and KidsDoc, a new iPhone and Android app for parents (available online).

Are You Sick?

David A Thompson, MD is the author of Adult HouseCalls Symptom Checker. He is a board-certified emergency medicine physician at Northwestern Memorial Hospital in Chicago. He has a national reputation in telephone triage, decision support tools, medical information technology and quality improvement. Adult HouseCalls Symptom Checker is a decision support tool for adults that has been reviewed and approved by adult physicians.

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