Drug interactions
Quinidine + Silodosin
Severity: Moderate
Quinidine and Silodosin: 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
Quinidine inhibits P-glycoprotein, which can increase silodosin absorption and exposure. Higher silodosin levels may cause orthostatic hypotension, dizziness and syncope.
What this interaction means in plain words
Quinidine and Silodosin 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.
Quinidine belongs to Anti Parasitic; Silodosin belongs to Genitourinary.
Why it happens
P-glycoprotein efflux inhibition by quinidine increases silodosin bioavailability.
What to do
Monitor blood pressure and orthostatic symptoms, particularly at initiation, and consider an alternative alpha-blocker if symptomatic hypotension occurs.
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 Silodosin
- Atazanavir + Silodosin Contraindicated
- Conivaptan + Silodosin Contraindicated
- Darunavir + Silodosin Contraindicated
- Fosamprenavir + Silodosin Contraindicated
- Indinavir + Silodosin Contraindicated
- Itraconazole + Silodosin Contraindicated
Other interactions of Quinidine
- Adagrasib + Quinidine Contraindicated
- Arsenic trioxide + Quinidine Contraindicated
- Artemether / lumefantrine + Quinidine Contraindicated
- Chloroquine + Quinidine Contraindicated
- Dofetilide + Quinidine Contraindicated
- Dronedarone + Quinidine Contraindicated
Frequently asked questions
Can I take Quinidine with Silodosin?
MediHelp rates the interaction as moderate. Quinidine and Silodosin 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. Quinidine inhibits P-glycoprotein, which can increase silodosin absorption and exposure. Higher silodosin levels may cause orthostatic hypotension, dizziness and syncope.
How serious is the interaction between Quinidine and Silodosin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor blood pressure and orthostatic symptoms, particularly at initiation, and consider an alternative alpha-blocker if symptomatic hypotension occurs.
What other medicines interact with Silodosin?
MediHelp also lists interactions of Silodosin with, for example, Atazanavir, Conivaptan, Darunavir. The full list is on the Silodosin page.
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