Tapering Dextromethorphan
Critical Clarification
Dextromethorphan used as a cough suppressant does not require a formal tapering protocol. Patients taking dextromethorphan solely for cough suppression at standard over-the-counter doses (typically 10-30 mg every 4-6 hours) can discontinue abruptly without risk of withdrawal symptoms, as this medication does not cause physical dependence at therapeutic doses for cough suppression 1.
When Tapering May Be Necessary
Tapering should only be considered for patients who have been using dextromethorphan in non-standard contexts:
High-Dose Recreational Use
- Patients who have been abusing dextromethorphan at supratherapeutic doses (often 200-1500 mg) for its dissociative effects may experience psychological withdrawal symptoms 1
- In these cases, gradual dose reduction over 2-4 weeks is reasonable, though no formal evidence-based protocol exists
- Monitor for psychological symptoms including dysphoria, anxiety, and drug craving
Dextromethorphan-Bupropion Combination (Auvelity)
- When discontinuing the FDA-approved dextromethorphan-bupropion formulation for depression, follow antidepressant discontinuation principles 1
- The bupropion component is the primary concern for withdrawal, not the dextromethorphan
- Gradual tapering over several weeks to months may be appropriate, though specific protocols for this combination are not yet established 1
Dextromethorphan-Quinidine Combination (Nuedexta)
- For pseudobulbar affect treatment, gradual discontinuation over 1-2 weeks is prudent
- No formal withdrawal syndrome has been documented, but abrupt cessation may lead to return of symptoms 1
Important Caveats
The evidence provided primarily addresses opioid, benzodiazepine, and antidepressant tapering—not dextromethorphan specifically. While dextromethorphan has NMDA receptor antagonist and sigma-1 receptor agonist properties, it does not produce the same physical dependence as opioids or benzodiazepines at therapeutic doses 1.
For standard cough suppressant use: no taper is needed. Simply discontinue when cough resolves 1.
If there is concern about substance use disorder involving dextromethorphan, refer to addiction medicine specialists rather than attempting office-based tapering, as the psychological dependence component requires specialized treatment.