Drug interactions
Mirabegron + Thioridazine
Severity: Major
Mirabegron and Thioridazine: major 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
Thioridazine is metabolised by CYP2D6, and higher exposure increases the risk of QT prolongation and ventricular arrhythmias. Mirabegron inhibits CYP2D6 and can raise thioridazine levels, and thioridazine labeling contraindicates drugs that inhibit its metabolism.
What this interaction means in plain words
Mirabegron and Thioridazine 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.
Mirabegron belongs to Genitourinary; Thioridazine belongs to Central Nervous System.
Why it happens
Mirabegron inhibits CYP2D6, reducing thioridazine clearance and increasing exposure.
What to do
Avoid the combination where possible and use an alternative bladder agent. If it cannot be avoided, obtain an ECG and monitor QTc and electrolytes.
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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Other interactions of Mirabegron
- Digoxin + Mirabegron Major
- Flecainide + Mirabegron Major
- Mirabegron + Propafenone Major
- Amitriptyline + Mirabegron Moderate
- Amoxapine + Mirabegron Moderate
- Atomoxetine + Mirabegron Moderate
Other interactions of Thioridazine
- Abiraterone + Thioridazine Contraindicated
- Adagrasib + Thioridazine Contraindicated
- Amiodarone + Thioridazine Contraindicated
- Amisulpride + Thioridazine Contraindicated
- Amitriptyline + Thioridazine Contraindicated
- Amoxapine + Thioridazine Contraindicated
Frequently asked questions
Can I take Mirabegron with Thioridazine?
MediHelp rates the interaction as major. Mirabegron and Thioridazine 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. Thioridazine is metabolised by CYP2D6, and higher exposure increases the risk of QT prolongation and ventricular arrhythmias. Mirabegron inhibits CYP2D6 and can raise thioridazine levels, and thioridazine labeling contraindicates drugs that inhibit its metabolism.
How serious is the interaction between Mirabegron and Thioridazine?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination where possible and use an alternative bladder agent. If it cannot be avoided, obtain an ECG and monitor QTc and electrolytes.
What other medicines interact with Mirabegron?
MediHelp also lists interactions of Mirabegron with, for example, Digoxin, Flecainide, Propafenone. The full list is on the Mirabegron page.
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