Dextromethorphan is an antitussive (cough suppressant) available in over-the-counter (OTC) medicines that control coughs due to minor throat and bronchial irritation, as may occur with the common cold or inhaled irritants. Dextromethorphan can be the only active ingredient in a cough suppressant medicine or can be found in medicines that treat the multiple symptoms of cough and cold, and cough suppressant lozenges.

Symptoms Treated

Symptoms Treated

More specifically: 

Coughing, Throat irritation, Cold symptoms

Dosing Information

Different types of products containing this active ingredient have different strengths. That’s why it is always important to read and follow the Drug Facts label. Most medicines warn against use of an active ingredient for longer than 7-10 days. Stop use and ask a doctor if symptoms persist.

Safety Guide

Safety Guide

Dextromethorphan is approved by the U.S. Food and Drug Administration (FDA) and is safe and effective when used according to the Drug Facts label.

Ask a healthcare provider before use if:

  • You are pregnant or breastfeeding.

Do not use if:

  • You are currently taking a prescription monoamine oxidase inhibitor (MAOI) (usually contained in drugs for depression, psychiatric or emotional conditions, or Parkinson’s disease) or if you stopped taking an MAOI less than two weeks ago.
  • You have a chronic cough due to smoking, asthma, bronchitis, or emphysema, or if your cough is accompanied by excessive congestion (mucus), unless a healthcare provider tells you to.
  • Do not give a medicine containing dextromethorphan to a child under the age of 4.
  • Do not give a cough suppressant lozenge to a child unless able to safely dissolve a lozenge in his or her mouth without choking.

Stop use and ask a doctor if:

  • Your cough lasts for more than one week, comes back, or is accompanied by a fever, rash, or persistent headache.
  • You take too much. Immediately contact a healthcare provider or the poison control national helpline at 800.222.1222.

What are the side effects of dextromethorphan?

  • Drowsiness may occur. You should avoid alcoholic drinks.
  • Nervousness or restlessness may occur. You should avoid taking diet pills, caffeine pills, or other stimulants.

Attention Parents: While cough suppressant medicines containing dextromethorphan are non-narcotic and non-addictive, dextromethorphan sometimes is abused by young people in an attempt to get high. Reports indicate that teens looking to get high may take 25 to 50 times the recommended amount on the label to get high. Be aware of the possibility for abuse. More information is available at