Dextromethorphan
Dextromethorphan (DXM) is a widely used cough suppressant found in many over-the-counter medications, typically available as liquids, tablets, or capsules. Initially developed in the 1950s as a safer alternative to codeine-based cough syrups, DXM was long regarded as having low potential for abuse. However, at higher doses, it can produce dissociative and hallucinogenic effects, leading to increased misuse, particularly among younger populations. DXM acts on the brain by inhibiting NMDA receptors, which can alter perception and cognitive function, resulting in a range of subjective effects, including euphoria, hallucinations, and confusion.
Abuse of DXM can lead to significant health risks, especially when combined with other medications, potentially causing serious side effects such as hypertension and liver damage. Despite a decline in misuse due to public awareness campaigns, DXM remains responsible for numerous emergency room visits each year, especially among individuals aged sixteen to twenty-five. The potential for both acute and long-term psychological issues associated with abuse is a significant concern for health professionals and communities alike.
Dextromethorphan
ALSO KNOWN AS: CCC; DXM; poor man’s PCP; robo; skittles; triple C
DEFINITION: Dextromethorphan is a cough suppressant contained in dozens of over-the-counter medications, and it is increasingly being abused for its dissociative opioid effects.
STATUS: Legal in many countries worldwide
CLASSIFICATION: Unclassified
SOURCE: Widely produced as an additive to cough and cold preparations in the form of liquids, tablets, and capsules
TRANSMISSION ROUTE: Oral ingestion
History of Use
Familiar since the 1950s to people with coughs and colds, dextromethorphan (DXM) was originally developed as a safer alternative to the codeine cough syrups that were then common. DXM was long considered devoid of any potential for abuse, even though it is an opioid derivative. When taken at higher than recommended doses, however, DXM produces dissociative hallucinogenic effects. As a result, since the 1990s, abuse of over-the-counter (OTC) medications, including DXM, has grown. Only alcohol, opioids, tobacco, and cannabis are abused more frequently than OTC medications.
Effects and Potential Risks
DXM acts in the brain and spinal cord to inhibit receptors for N-methyl-d-aspartate (NMDA). As such, DXM—along with other NMDA antagonists—alters the distribution of the neurotransmitter glutamate throughout the brain, altering the user’s perception of pain, understanding of the environment, and memory. Subjective effects include euphoria, hallucinations, paranoid delusions, confusion, agitation, altered moods, difficulty concentrating, nightmares, catatonia, ataxia, and anesthesia. The typical clinical presentation of DXM intoxication involves hyperexcitability, lethargy, ataxia, slurred speech, sweating, hypertension, and nystagmus.
Abusers of DXM describe the following dose-dependent plateaus: mild stimulation at a dosage between 100 and 200 milligrams (mg); euphoria and hallucinations begin at a dosage of between 200 and 400 mg; between 300 and 600 mg, the user will experience distorted visual perception and loss of motor coordination; and between 500 and 1,500 mg, the user will experience dissociative sedation. These effects are only experienced when a person has consumed vastly more DXM than recommended for regular therapeutic use.
This practice is particularly dangerous when DXM is combined with other active ingredients, such as pseudoephedrine, acetaminophen, or guaifenesin. Health risks associated with abusing these latter substances include increased blood pressure (pseudoephedrine), potential liver damage (acetaminophen), and central nervous system toxicity, cardiovascular toxicity, and anticholinergic toxicity (antihistamines).
Thanks to public awareness campaigns about the misuse of DXM and other OTC medications, abuse of the substance has declined since 2006. Still, misuse of DXM leads to over 6,000 emergency room visits each year, with the majority of patients between the ages of sixteen and twenty-five. It is not just the acute effects of DXM overdose that remain concerning. Misuse of DXM can lead to long-term behavioral changes and psychological issues. Individuals who abuse DXM are more likely to engage in other risky activities and can reach a level of intoxication that puts others in danger as well.
Bibliography
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