Drug interactions
Itraconazole + Sildenafil
Severity: Major
Itraconazole and Sildenafil: 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
Itraconazole is a strong CYP3A4 inhibitor and substantially raises sildenafil exposure. This increases the risk of hypotension, syncope, headache, visual disturbances and prolonged erections.
What this interaction means in plain words
Itraconazole and Sildenafil 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.
Itraconazole belongs to Anti Fungals; Sildenafil belongs to Genitourinary.
Why it happens
Strong inhibition of CYP3A4-mediated first-pass and systemic metabolism of sildenafil.
What to do
For erectile dysfunction, start with a reduced sildenafil dose such as 25 mg and monitor blood pressure and adverse effects. Avoid the combination when sildenafil is used for pulmonary arterial hypertension.
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 Sildenafil
- Amyl nitrite + Sildenafil Contraindicated
- Atazanavir + Sildenafil Contraindicated
- Cobicistat + Sildenafil Contraindicated
- Elvitegravir / cobicistat / emtricitabine / tenofovir df + Sildenafil Contraindicated
- Glyceryl trinitrate pr + Sildenafil Contraindicated
- Isosorbide dinitrate + Sildenafil Contraindicated
Other interactions of Itraconazole
- Alfuzosin + Itraconazole Contraindicated
- Alprazolam + Itraconazole Contraindicated
- Avanafil + Itraconazole Contraindicated
- Conivaptan + Itraconazole Contraindicated
- Dihydroergotamine intranasal + Itraconazole Contraindicated
- Dihydroergotamine + Itraconazole Contraindicated
Frequently asked questions
Can I take Itraconazole with Sildenafil?
MediHelp rates the interaction as major. Itraconazole and Sildenafil 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. Itraconazole is a strong CYP3A4 inhibitor and substantially raises sildenafil exposure. This increases the risk of hypotension, syncope, headache, visual disturbances and prolonged erections.
How serious is the interaction between Itraconazole and Sildenafil?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: For erectile dysfunction, start with a reduced sildenafil dose such as 25 mg and monitor blood pressure and adverse effects. Avoid the combination when sildenafil is used for pulmonary arterial hypertension.
What other medicines interact with Sildenafil?
MediHelp also lists interactions of Sildenafil with, for example, Amyl nitrite, Atazanavir, Cobicistat. The full list is on the Sildenafil page.
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