Drug interactions
Desvenlafaxine + Thioridazine
Severity: Major
Desvenlafaxine 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 metabolized by CYP2D6 and causes dose-related QT prolongation, so even a modest rise in its levels is a concern. Desvenlafaxine's weak CYP2D6 inhibition, plus its own minor QT effects, could raise the risk of serious arrhythmia.
What this interaction means in plain words
Desvenlafaxine 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.
Desvenlafaxine belongs to Central Nervous System; Thioridazine belongs to Central Nervous System.
Why it happens
Weak CYP2D6 inhibition raises thioridazine levels, with additive QT prolongation.
What to do
Avoid the combination where possible and choose an antipsychotic with less QT risk. If used together, monitor ECG and electrolytes closely.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Desvenlafaxine and Thioridazine, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
Other interactions of Desvenlafaxine
- Desvenlafaxine + Isocarboxazid Contraindicated
- Desvenlafaxine + Methylene blue Contraindicated
- Desvenlafaxine + Phenelzine Contraindicated
- Desvenlafaxine + Rasagiline Contraindicated
- Desvenlafaxine + Safinamide Contraindicated
- Desvenlafaxine + Selegiline Contraindicated
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 Desvenlafaxine with Thioridazine?
MediHelp rates the interaction as major. Desvenlafaxine 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 metabolized by CYP2D6 and causes dose-related QT prolongation, so even a modest rise in its levels is a concern. Desvenlafaxine's weak CYP2D6 inhibition, plus its own minor QT effects, could raise the risk of serious arrhythmia.
How serious is the interaction between Desvenlafaxine 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 choose an antipsychotic with less QT risk. If used together, monitor ECG and electrolytes closely.
What other medicines interact with Desvenlafaxine?
MediHelp also lists interactions of Desvenlafaxine with, for example, Isocarboxazid, Methylene blue, Phenelzine. The full list is on the Desvenlafaxine page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
