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Drug interactions

Nelfinavir + Vardenafil

Severity: Major

Nelfinavir 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

Nelfinavir inhibits CYP3A4 and can raise vardenafil exposure considerably. This increases the likelihood of hypotension, syncope and QT effects.

What this interaction means in plain words

Nelfinavir 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.

Nelfinavir belongs to Anti Virals; Vardenafil belongs to Genitourinary.

Evidence level: Moderate

Why it happens

CYP3A4 inhibition by nelfinavir reduces vardenafil clearance.

What to do

Limit vardenafil to a low dose (2.5 mg) with extended intervals and monitor blood pressure.

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?

Bring a full list of your medicines, including over-the-counter products, supplements and herbal remedies, to every pharmacy visit.

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Frequently asked questions

Can I take Nelfinavir with Vardenafil?

MediHelp rates the interaction as major. Nelfinavir 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. Nelfinavir inhibits CYP3A4 and can raise vardenafil exposure considerably. This increases the likelihood of hypotension, syncope and QT effects.

How serious is the interaction between Nelfinavir 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: Limit vardenafil to a low dose (2.5 mg) with extended intervals and monitor blood pressure.

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

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