Drug interactions
Lonafarnib + Orphenadrin
Severity: Moderate
Lonafarnib and Orphenadrin: moderate 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
Lonafarnib is a sensitive CYP3A substrate, and orphenadrine is a weak CYP3A inhibitor in some references. Coadministration may raise lonafarnib exposure and its adverse effects, including gastrointestinal toxicity and possible effects on cardiac rhythm.
What this interaction means in plain words
Lonafarnib and Orphenadrin can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Lonafarnib belongs to Miscellaneous; Orphenadrin belongs to Musculoskeletal.
Why it happens
Possible weak inhibition of CYP3A4-mediated metabolism of lonafarnib by orphenadrine.
What to do
Prefer an alternative muscle relaxant if possible. If coadministered, keep lonafarnib at the starting dose and monitor for palpitations, syncope and gastrointestinal toxicity.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Lonafarnib and Orphenadrin, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
Other interactions of Orphenadrin
Other interactions of Lonafarnib
- Alfuzosin + Lonafarnib Contraindicated
- Amobarbital + Lonafarnib Contraindicated
- Apalutamide + Lonafarnib Contraindicated
- Bosentan + Lonafarnib Contraindicated
- Carbamazepine + Lonafarnib Contraindicated
- Clarithromycin + Lonafarnib Contraindicated
Frequently asked questions
Can I take Lonafarnib with Orphenadrin?
MediHelp rates the interaction as moderate. Lonafarnib and Orphenadrin can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Lonafarnib is a sensitive CYP3A substrate, and orphenadrine is a weak CYP3A inhibitor in some references. Coadministration may raise lonafarnib exposure and its adverse effects, including gastrointestinal toxicity and possible effects on cardiac rhythm.
How serious is the interaction between Lonafarnib and Orphenadrin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Prefer an alternative muscle relaxant if possible. If coadministered, keep lonafarnib at the starting dose and monitor for palpitations, syncope and gastrointestinal toxicity.
What other medicines interact with Orphenadrin?
MediHelp also lists interactions of Orphenadrin with, for example, Alfentanil, Amobarbital, Benzhydrocodone / acetaminophen. The full list is on the Orphenadrin page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
