Drug interactions
Lonafarnib + Vardenafil
Severity: Major
Lonafarnib and Vardenafil: major interaction.
Last updated Sources: US FDA label
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 strong CYP3A4 inhibitor and can substantially increase exposure to vardenafil. This increases the risk of hypotension, syncope and QT prolongation.
What this interaction means in plain words
Lonafarnib and Vardenafil 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.
Lonafarnib belongs to Miscellaneous; Vardenafil belongs to Genitourinary.
Why it happens
Strong CYP3A4 inhibition by lonafarnib decreases vardenafil metabolism.
What to do
Avoid the combination where possible; if unavoidable, use a markedly reduced vardenafil dose and monitor blood pressure and ECG.
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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References
Other interactions of Vardenafil
- Amyl nitrite + Vardenafil Contraindicated
- Glyceryl trinitrate pr + Vardenafil Contraindicated
- Isosorbide dinitrate + Vardenafil Contraindicated
- Isosorbide mononitrate + Vardenafil Contraindicated
- Nicorandil + Vardenafil Contraindicated
- Nitroglycerin po + Vardenafil Contraindicated
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 Vardenafil?
MediHelp rates the interaction as major. Lonafarnib and Vardenafil 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. Lonafarnib is a strong CYP3A4 inhibitor and can substantially increase exposure to vardenafil. This increases the risk of hypotension, syncope and QT prolongation.
How serious is the interaction between Lonafarnib and Vardenafil?
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 where possible; if unavoidable, use a markedly reduced vardenafil dose and monitor blood pressure and ECG.
What other medicines interact with Vardenafil?
MediHelp also lists interactions of Vardenafil with, for example, Amyl nitrite, Glyceryl trinitrate pr, Isosorbide dinitrate. The full list is on the Vardenafil page.
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