Dextromethorphan Dosage Table

Dextromethorphan Dosage
Child’s weight 16 – 31 lbs. 32 – 47 lbs. 48 – 63 lbs. 64 – 79 lbs. 80 – 95 lbs. 96 – 129 lbs. Over 130 lbs.
Liquid 5 mg/ 1 teaspoon (tsp) ½ 1 2 3
Liquid 5 mg/ 5 milliliters (ml) 2.5 5 7.5 10 12.5 15
Liquid 7.5 mg/1 teaspoon (tsp) 1 1 2 3
Liquid 7.5 mg/ 5 milliliters (ml) 5 5 7.5 10 15
Liquid 10 mg/1 teaspoon (tsp) 1 1 2
Liquid 10 mg/ 5 milliliters (ml) 5 5 7.5 10

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 six to eight 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