Drug interactions
Istradefylline + Vardenafil
Severity: Minor
Istradefylline and Vardenafil: minor 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
Istradefylline at 40 mg daily raised exposure to CYP3A4 substrates, while 20 mg daily did not show this effect. Vardenafil exposure may therefore rise at the higher istradefylline dose, increasing vasodilatory effects.
What this interaction means in plain words
Istradefylline and Vardenafil have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Istradefylline belongs to Central Nervous System; Vardenafil belongs to Genitourinary.
Why it happens
Dose-dependent CYP3A4 inhibition by istradefylline reduces vardenafil clearance.
What to do
With istradefylline 40 mg daily, consider reducing the vardenafil dose and monitor blood pressure and adverse effects.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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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 Istradefylline
Frequently asked questions
Can I take Istradefylline with Vardenafil?
MediHelp rates the interaction as minor. Istradefylline and Vardenafil have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Istradefylline at 40 mg daily raised exposure to CYP3A4 substrates, while 20 mg daily did not show this effect. Vardenafil exposure may therefore rise at the higher istradefylline dose, increasing vasodilatory effects.
How serious is the interaction between Istradefylline and Vardenafil?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: With istradefylline 40 mg daily, consider reducing the vardenafil dose and monitor blood pressure and adverse effects.
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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