Dextromethorphan Dosage Table

Dextromethorphan Dosage Table

Child's weight (pounds) 16-31 32-47 48-63 64-79 80-95 96-129 130+ lbs
Liquid 5 mg/5 ml (tsp) ½ 1 2 3 -- tsp
Liquid 5 mg/ 5 milliliters (ml) 2.5 5 7.5 10 12.5 15 -- ml
Liquid 7.5 mg/5 ml (tsp) -- -- 1 1 2 3 tsp
Liquid 7.5 mg/ 5 milliliters (ml) -- -- 5 5 7.5 10 15 ml
Liquid 10 mg/1 teaspoon (tsp) -- -- -- 1 1 2 tsp
Liquid 10 mg/5 ml (ml) -- -- -- 5 5 7.5 10 ml

Indication: Cough suppressant. Dextromethorphan (DM) is present in most cough syrups.

Table Notes:

  • AGE LIMIT: Don’t use under 4 years of age.
  • OVER 4 YEARS OF AGE: NOT recommended as primary treatment of cough. Use HONEY instead.
  • 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.
  • FREQUENCY: Repeat every 6-8 hours as needed
  • ADULT DOSE: 20 mg

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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