Drug interactions
Ritonavir + Vardenafil
Severity: Major
Ritonavir and Vardenafil: 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
Ritonavir is a potent CYP3A4 inhibitor and raises vardenafil exposure many-fold with a prolonged half-life. Severe hypotension, syncope, priapism and QT prolongation can result.
What this interaction means in plain words
Ritonavir 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.
Ritonavir belongs to Anti Virals; Vardenafil belongs to Genitourinary.
Why it happens
Strong CYP3A4 inhibition by ritonavir markedly reduces vardenafil clearance.
What to do
Do not exceed vardenafil 2.5 mg in 72 hours and monitor blood pressure; consider an alternative agent.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Ritonavir and Vardenafil, 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 14 days on the web. No card needed.
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 Ritonavir
- Alfuzosin + Ritonavir Contraindicated
- Amiodarone + Ritonavir Contraindicated
- Avanafil + Ritonavir Contraindicated
- Colchicine + Ritonavir Contraindicated
- Dronedarone + Ritonavir Contraindicated
- Eletriptan + Ritonavir Contraindicated
Frequently asked questions
Can I take Ritonavir with Vardenafil?
MediHelp rates the interaction as major. Ritonavir 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. Ritonavir is a potent CYP3A4 inhibitor and raises vardenafil exposure many-fold with a prolonged half-life. Severe hypotension, syncope, priapism and QT prolongation can result.
How serious is the interaction between Ritonavir 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: Do not exceed vardenafil 2.5 mg in 72 hours and monitor blood pressure; consider an alternative agent.
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.
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.
