Drug interactions
Arsenic trioxide + Paroxetine
Severity: Major
Arsenic trioxide and Paroxetine: major interaction.
Last updated Sources: UK SmPC
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
Arsenic trioxide has a boxed warning for QT prolongation and torsades de pointes, and its label advises avoiding other QT-prolonging drugs. Paroxetine has relatively low QT liability but may still add to risk in this vulnerable setting.
What this interaction means in plain words
Arsenic trioxide and Paroxetine 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.
Arsenic trioxide belongs to Oncology; Paroxetine belongs to Central Nervous System.
Why it happens
Additive effects on cardiac repolarization.
What to do
Check baseline ECG and electrolytes and maintain potassium and magnesium in range. Prefer an antidepressant with minimal QT effect, and monitor ECG throughout arsenic therapy if paroxetine is continued.
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 Arsenic trioxide and Paroxetine, 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.
References
- Paroxetine 10 mg Tablets - SmPC sections 4.3/4.5 (class statement: drugs which prolong the QTc interval; "The risk of QTc prolongation and/or ventricular arrhythmias (e.g. TdP) may be increased with concomitant use of other drugs which prolong the QTc interval (e.g.") — electronic medicines compendium (UK SmPC)
Other interactions of Paroxetine
- Isocarboxazid + Paroxetine Contraindicated
- Methylene blue + Paroxetine Contraindicated
- Paroxetine + Phenelzine Contraindicated
- Paroxetine + Pimozide Contraindicated
- Paroxetine + Procarbazine Contraindicated
- Paroxetine + Selegiline Contraindicated
Other interactions of Arsenic trioxide
- Amiodarone + Arsenic trioxide Contraindicated
- Amisulpride + Arsenic trioxide Contraindicated
- Arsenic trioxide + Clomipramine Contraindicated
- Arsenic trioxide + Dronedarone Contraindicated
- Arsenic trioxide + Fluphenazine Contraindicated
- Arsenic trioxide + Gemifloxacin Contraindicated
Frequently asked questions
Can I take Arsenic trioxide with Paroxetine?
MediHelp rates the interaction as major. Arsenic trioxide and Paroxetine 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. Arsenic trioxide has a boxed warning for QT prolongation and torsades de pointes, and its label advises avoiding other QT-prolonging drugs. Paroxetine has relatively low QT liability but may still add to risk in this vulnerable setting.
How serious is the interaction between Arsenic trioxide and Paroxetine?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Check baseline ECG and electrolytes and maintain potassium and magnesium in range. Prefer an antidepressant with minimal QT effect, and monitor ECG throughout arsenic therapy if paroxetine is continued.
What other medicines interact with Paroxetine?
MediHelp also lists interactions of Paroxetine with, for example, Isocarboxazid, Methylene blue, Phenelzine. The full list is on the Paroxetine 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.
