Drug interactions
Posaconazole + Sildenafil
Severity: Major
Posaconazole 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
Posaconazole is a strong CYP3A4 inhibitor and can raise sildenafil exposure considerably. This increases the risk of hypotension, headache, visual disturbance and priapism-related effects.
What this interaction means in plain words
Posaconazole 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.
Posaconazole belongs to Anti Fungals; Sildenafil belongs to Genitourinary.
Why it happens
Inhibition of CYP3A4-mediated first-pass and hepatic metabolism of sildenafil.
What to do
Start with a reduced sildenafil dose (for erectile dysfunction, 25 mg) and avoid repeated dosing. Do not combine with sildenafil for pulmonary hypertension unless dose is lowered and blood pressure is monitored.
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 Posaconazole
- Artemether + Posaconazole Contraindicated
- Avanafil + Posaconazole Contraindicated
- Cobimetinib + Posaconazole Contraindicated
- Conivaptan + Posaconazole Contraindicated
- Dihydroergotamine intranasal + Posaconazole Contraindicated
- Dihydroergotamine + Posaconazole Contraindicated
Frequently asked questions
Can I take Posaconazole with Sildenafil?
MediHelp rates the interaction as major. Posaconazole 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. Posaconazole is a strong CYP3A4 inhibitor and can raise sildenafil exposure considerably. This increases the risk of hypotension, headache, visual disturbance and priapism-related effects.
How serious is the interaction between Posaconazole 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: Start with a reduced sildenafil dose (for erectile dysfunction, 25 mg) and avoid repeated dosing. Do not combine with sildenafil for pulmonary hypertension unless dose is lowered and blood pressure is monitored.
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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