U01.16.050 Dextromethorphan

Dextromethorphan is a commonly used antitussive (cough suppressant) that is effective in treating coughs due to its action on specific receptors in the brain. It is a synthetic analog of codeine, offering some similar effects but with fewer risks when used appropriately.

Mechanism of Action

Antitussive Action:
Dextromethorphan works by antagonizing NMDA (N-methyl-D-aspartate) glutamate receptors in the brain. By inhibiting these receptors, it helps suppress the cough reflex.
Mild Opioid Effect:
As a synthetic analog of codeine, dextromethorphan can produce a mild opioid effect, especially when used in excess.

Clinical Uses

Cough Suppression:
Dextromethorphan is primarily used to relieve non-productive coughs, making it easier for patients to rest and recover.

Side Effects and Risks

Overdose and Treatment:
In cases of overdose, dextromethorphan can produce significant effects, and naloxone, an opioid antagonist, can be administered as a treatment.
Abuse Potential:
Although it has a mild abuse potential, excessive use can lead to undesirable effects due to its opioid-like properties.
Serotonin Syndrome:
Combining dextromethorphan with other serotonergic agents (such as certain antidepressants) may lead to serotonin syndrome, a potentially life-threatening condition characterized by confusion, rapid heart rate, and high blood pressure.

Points to Remember

Dextromethorphan is a synthetic analog of codeine and acts as an NMDA receptor antagonist.
It has a mild opioid effect and a low potential for abuse.
Naloxone can be used in cases of overdose.
Combining with serotonergic agents may lead to serotonin syndrome.

Table: Dextromethorphan Summary

Aspect	Details
Class	Antitussive
Mechanism of Action	NMDA receptor antagonist
Analog	Synthetic codeine analog
Potential Effects	Mild opioid effect in excess
Overdose Treatment	Naloxone
Abuse Potential	Mild
Serotonin Syndrome Risk	Possible when combined with serotonergic agents

Bibliography

American Pharmacists Association. (2023). Dextromethorphan: Clinical Overview and Usage. Retrieved from pharmacist.com.
Mayo Clinic. (2023). Dextromethorphan – Drug Information. Retrieved from mayoclinic.org.
National Institute on Drug Abuse. (2023). Dextromethorphan and Abuse Potential. Retrieved from drugabuse.gov.

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