Drug interactions
Bosentan + Sildenafil
Severity: Moderate
Bosentan and Sildenafil: 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
Bosentan induces CYP3A4 and CYP2C9, which lowers sildenafil exposure. Sildenafil levels fall by a moderate amount, and bosentan exposure may rise slightly, so efficacy of sildenafil may be reduced.
What this interaction means in plain words
Bosentan and Sildenafil 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.
Bosentan belongs to Miscellaneous; Sildenafil belongs to Genitourinary.
Why it happens
Bosentan induces CYP3A4, increasing the metabolic clearance of sildenafil.
What to do
In pulmonary arterial hypertension this combination is used deliberately without dose change; monitor clinical response. For erectile dysfunction, watch for lack of efficacy and adjust therapy if needed.
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 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 Bosentan
- Bosentan + Cyclosporin Contraindicated
- Bosentan + Glibenclamide Contraindicated
- Bosentan + Glyburide-metformin Contraindicated
- Bosentan + Lonafarnib Contraindicated
- Bosentan + Sparsentan Contraindicated
- Artemether / lumefantrine + Bosentan Major
Frequently asked questions
Can I take Bosentan with Sildenafil?
MediHelp rates the interaction as moderate. Bosentan and Sildenafil 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. Bosentan induces CYP3A4 and CYP2C9, which lowers sildenafil exposure. Sildenafil levels fall by a moderate amount, and bosentan exposure may rise slightly, so efficacy of sildenafil may be reduced.
How serious is the interaction between Bosentan and Sildenafil?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: In pulmonary arterial hypertension this combination is used deliberately without dose change; monitor clinical response. For erectile dysfunction, watch for lack of efficacy and adjust therapy if needed.
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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