dextromethorphan

Dextromethorphan is a medication used to control coughs caused by the common cold, flu, or other conditions. Dextromethorphan can temporarily relieve cough, but does not treat the cause of the cough or help with recovery.

Dextromethorphan is available over-the-counter under multiple brand names. Dextromethorphan is also often combined with other medications such as antihistamines and painkillers (analgesics).

Dextromethorphan suppresses cough by reducing the sensitivity of cough receptors in the brain region that stimulate the cough reflex and preventing the transmission of cough impulses. Dextromethorphan is a non-opioid drug derived from levorphanol, an opioid analgesic, and is structurally similar to opioid drugs such as codeine.

Dextromethorphan does not interact with opioid receptors and hence, does not have analgesic or addictive properties, however, it increases the levels of chemical messengers such as serotonin, and has the potential for abuse.

• Do not take dextromethorphan if you are allergic to it or any of its components
• Do not use dextromethorphan simultaneously with monoamine oxidase inhibitors (MAOIs), which prevent break down of brain chemicals; can lead to serotonin syndrome
• Do not administer dextromethorphan OTC to children younger than 4 years; it can cause serious side effects; use with caution in children of 4-11 years
• Dextromethorphan may cause hallucinations, confusion, agitation, overactive reflexes, shivering, muscle twitching and rapid heart rate
• Do not take for persistent or chronic cough associated with smoking, asthma, or emphysema, or if you have excessive phlegm, unless prescribed by your doctor; may slow respiration rate
• Some brands of dextromethorphan may contain aspartame, a source of the amino acid phenylalanine; use with caution in patients with phenylketonuria, an inherited condition that causes buildup of phenylalanine
• Use with caution in patients who are sedated, debilitated or confined to supine position

Common side effects of dextromethorphan include:

• Dizziness
• Lightheadedness
• Drowsiness
• Sedation
• Nervousness
• Restlessness
• Confusion
• Nausea
• Vomiting
• Stomach pain
• Constipation

This is not a complete list of all side effects or adverse reactions that may occur from the use of this drug.

Call your doctor for medical advice about serious side effects or adverse reactions. You may also report side effects or health problems to the FDA at 1-800-FDA-1088.

Tablet

• 15 mg

Capsule

• 15 mg
• 25 mg

Gel, oral

• 7.5 mg/5 ml

Liquid, oral

• 7.5 mg/5 ml
• 10 mg/5 ml
• 15 mg/5 ml

Syrup, oral

• 5 mg/5 ml
• 7.5 mg/5 ml
• 10 mg/5 ml
• 15 mg/5 ml
• 20 mg/15 ml

Liquid, extended-release

• 30 mg/5 ml

Lozenge

• 5 mg
• 7.5 mg
• 15 mg

Strip, oral

• 7.5 mg

Adult

Cough

• Liquid and syrup: 10-20 mg orally every 4 hours or 30 mg every 6-8 hours
• Gel: 30 mg orally every 6-8 hours, not to exceed 120 mg per day
• Extended-release: 60 mg orally every 12 hours, not to exceed 120 mg per day
• Lozenges: 5-15 mg orally every 1-4 hours, not to exceed 120 mg per day
• Strips: 30 mg orally every 6-8 hours, not to exceed 120 mg per day

Dosing considerations

• Abuse potential is much lower than codeine
• About 15-30 mg dextromethorphan is equal to 8-15 mg codeine as an antitussive

Pediatric

Cough

• Children under 4 years: prescription only

Extended-release:

• Children 4-6 years old: 15 mg orally twice daily, not to exceed 30 mg per day
• Children 6-12 years: 30 mg orally twice daily, not to exceed 60 mg per day
• Children over 12 years: 60 mg orally twice daily, not to exceed 120 mg per day

Liquid/Syrup

• Children 4-6 years old: 7.5 mg every 6-8 hours, not to exceed 30 mg per day
• Children 6-12 years old: 15 mg orally every 6-8 hours, not to exceed 60 mg per day
• Children over 12 years: 10-20 mg orally every 4 hours or 30 mg every 6-8 hours not to exceed 120 mg per day

Gel

• Children over 12 years: 30 mg every 6-8 hours, not to exceed 120 mg per day

Lozenges

• Children 6-12 years: 5-10 mg every 1-4 hours, not to exceed 60 mg per day
• Children over 12 years: 5-15 mg orally every 1-4 hours, not to exceed 120 mg per day

Strips

• Children 6-12 years: 15 mg orally every 6-8 hours, not to exceed 60 mg per day
• Children over 12 years: 30 mg orally every 6-8 hours, not to exceed 120 mg per day

Dosing Considerations

• Potential toxic doses children under 6 years: 10 mg/kg
• About 15-30 mg dextromethorphan is equal to 8-15 mg codeine as an antitussive

• Dextromethorphan is not addictive like opioid medications but has the potential for abuse. There have been reports of abuse of dextromethorphan-containing products, especially among teenagers.
• Overdose can cause severe side effects, particularly in children. In case of overdose, seek medical help or contact the Poison Control Center immediately.

Inform your doctor of all medications you are currently taking, who can advise you on any possible drug interactions. Never begin taking, suddenly discontinue, or change the dosage of any medication without your doctor’s recommendation.

• Severe Interactions of dextromethorphan include:
  • isocarboxazid
  • phenelzine
  • procarbazine
  • rasagiline
  • safinamide
  • selegiline
  • tranylcypromine
• Dextromethorphan has serious interactions with at least 34 different drugs.
• Dextromethorphan has moderate interactions with at least 58 different drugs.
• Dextromethorphan has mild interactions with at least 22 different drugs.

The drug interactions listed above are not all of the possible interactions or adverse effects. For more information on drug interactions, visit the RxList Drug Interaction Checker.

It is important to always tell your doctor, pharmacist, or health care provider of all prescription and over-the-counter medications you use, as well as the dosage for each, and keep a list of the information.

Check with your doctor or health care provider if you have any questions about the medication.

• There is insufficient information available on the use of dextromethorphan during pregnancy and breastfeeding.
• Check with your doctor before taking dextromethorphan if you are pregnant, plan to become pregnant or breastfeeding.

• Follow package instructions exactly while taking OTC drugs. Do not take higher or more frequent doses than recommended.
• Store dextromethorphan out of reach of children and dispose of unused medication carefully.
• Stop taking dextromethorphan and see your doctor if your cough does not get better within 7 days, goes away and comes back, or is accompanied by other symptoms such as fever, rash, or headache.