Drug interactions
Efavirenz + Vardenafil
Severity: Moderate
Efavirenz and Vardenafil: 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
Efavirenz is a CYP3A4 inducer (with mixed effects) and may lower vardenafil exposure, reducing erectile response. Both agents have also been associated with QT prolongation, though the additive effect is generally small at usual doses.
What this interaction means in plain words
Efavirenz and Vardenafil 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.
Efavirenz belongs to Anti Virals; Vardenafil belongs to Genitourinary.
Why it happens
Efavirenz induces CYP3A4-mediated metabolism of vardenafil, and both drugs may have modest additive effects on cardiac repolarization.
What to do
Assess erectile response and titrate vardenafil within the labeled dose range if efficacy is inadequate. Consider an ECG in patients with other QT risk factors.
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?
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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 Efavirenz
- Cobimetinib + Efavirenz Contraindicated
- Dienogest / estradiol valerate + Efavirenz Contraindicated
- Dihydroergotamine intranasal + Efavirenz Contraindicated
- Dihydroergotamine + Efavirenz Contraindicated
- Doravirine + Efavirenz Contraindicated
- Efavirenz + Elbasvir / grazoprevir Contraindicated
Frequently asked questions
Can I take Efavirenz with Vardenafil?
MediHelp rates the interaction as moderate. Efavirenz and Vardenafil 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. Efavirenz is a CYP3A4 inducer (with mixed effects) and may lower vardenafil exposure, reducing erectile response. Both agents have also been associated with QT prolongation, though the additive effect is generally small at usual doses.
How serious is the interaction between Efavirenz and Vardenafil?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Assess erectile response and titrate vardenafil within the labeled dose range if efficacy is inadequate. Consider an ECG in patients with other QT risk factors.
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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