Drug interactions
Arsenic trioxide + Promethazine
Severity: Major
Arsenic trioxide and Promethazine: 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
The concurrent use of promethazine and arsenic trioxide may lead to an increased risk of QTc interval prolongation, which can result in serious cardiac arrhythmias. Patients taking both medications should be closely monitored for any signs of cardiac complications.
What this interaction means in plain words
Arsenic trioxide and Promethazine 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; Promethazine belongs to Respiratory.
Why it happens
Both promethazine and arsenic trioxide are known to affect cardiac repolarization, contributing to the prolongation of the QTc interval.
What to do
It is advisable to avoid co-administration of these drugs whenever possible. If their use together is necessary, continuous cardiac monitoring is recommended to detect any potential arrhythmias promptly.
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 Promethazine, 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 Promethazine
- Cabergoline + Promethazine Contraindicated
- Dopamine + Promethazine Contraindicated
- Ibutilide + Promethazine Contraindicated
- Pimozide + Promethazine Contraindicated
- Promethazine + Thioridazine Contraindicated
- Alfentanil + Promethazine Major
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 Promethazine?
MediHelp rates the interaction as major. Arsenic trioxide and Promethazine 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. The concurrent use of promethazine and arsenic trioxide may lead to an increased risk of QTc interval prolongation, which can result in serious cardiac arrhythmias. Patients taking both medications should be closely monitored for any signs of cardiac complications.
How serious is the interaction between Arsenic trioxide and Promethazine?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: It is advisable to avoid co-administration of these drugs whenever possible. If their use together is necessary, continuous cardiac monitoring is recommended to detect any potential arrhythmias promptly.
What other medicines interact with Promethazine?
MediHelp also lists interactions of Promethazine with, for example, Cabergoline, Dopamine, Ibutilide. The full list is on the Promethazine 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.
