Dextromethorphan and Selegiline interaction
Dextromethorphan and Selegiline: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Dextromethorphan (Delsym) label · effective 2026-05-27
Warnings Do not use if you are now taking a prescription monoamine oxidase inhibitor (MAOI) (certain drugs for depression, psychiatric, or emotional conditions, or Parkinson's disease), or for 2 weeks after stopping the MAOI drug.
If you do not know if your prescription drug contains an MAOI, ask a doctor or pharmacist before taking this product.
From the Selegiline (ZELAPAR) label · effective 2021-06-01
• Concomitant use of dextromethorphan, because of reported episodes of psychosis or bizarre behavior.
ZELAPAR is contraindicated in patients using the following drugs: opioid drugs (e.g., meperidine, tramadol, methadone), MAO inhibitors including selective MAO-B inhibitors, dextromethorphan, St.
Therefore, in view of ZELAPAR’s MAO inhibitory activity, dextromethorphan should not be used concomitantly with ZELAPAR [see Contraindications (4) ] .
Dextromethorphan The combination of MAO inhibitors and dextromethorphan has been reported to cause brief episodes of psychosis or bizarre behavior.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.