Drug interactions
Dextromethorphan + Lorcaserin
Severity: Major
Dextromethorphan and Lorcaserin: major interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Lorcaserin is a serotonin 5-HT2C agonist and is also a CYP2D6 inhibitor, and dextromethorphan is serotonergic and a CYP2D6 substrate. The combination may increase the risk of serotonin syndrome and raise dextromethorphan levels.
What this interaction means in plain words
Dextromethorphan and Lorcaserin can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Why it happens
Additive serotonergic activity together with CYP2D6 inhibition by lorcaserin.
What to do
Avoid the combination if possible; if used, monitor closely for signs of serotonin syndrome and use the lowest dextromethorphan dose.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Dextromethorphan
- Dextromethorphan + Isocarboxazid Contraindicated
- Dextromethorphan + Linezolid Contraindicated
- Dextromethorphan + Phenelzine Contraindicated
- Dextromethorphan + Rasagiline Contraindicated
- Dextromethorphan + Safinamide Contraindicated
- Dextromethorphan + Selegiline Contraindicated
Frequently asked questions
Can I take Dextromethorphan with Lorcaserin?
MediHelp rates the interaction as major. Dextromethorphan and Lorcaserin can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Lorcaserin is a serotonin 5-HT2C agonist and is also a CYP2D6 inhibitor, and dextromethorphan is serotonergic and a CYP2D6 substrate. The combination may increase the risk of serotonin syndrome and raise dextromethorphan levels.
How serious is the interaction between Dextromethorphan and Lorcaserin?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination if possible; if used, monitor closely for signs of serotonin syndrome and use the lowest dextromethorphan dose.
What other medicines interact with Dextromethorphan?
MediHelp also lists interactions of Dextromethorphan with, for example, Isocarboxazid, Linezolid, Phenelzine. The full list is on the Dextromethorphan page.
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