Drug interactions
Terbutaline + Thioridazine
Severity: Major
Terbutaline 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 markedly prolongs the QT interval, and terbutaline can cause hypokalemia and tachycardia, both of which increase the risk of torsades de pointes. The combination may result in life-threatening ventricular arrhythmia.
What this interaction means in plain words
Terbutaline 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.
Terbutaline belongs to Respiratory; Thioridazine belongs to Central Nervous System.
Why it happens
Additive proarrhythmic effects from thioridazine QT prolongation and beta-2 agonist-induced hypokalemia and sympathetic stimulation.
What to do
Avoid the combination where possible and prefer an alternative bronchodilator route such as inhaled therapy at the lowest effective dose. If used, monitor ECG and serum potassium and correct electrolyte disturbances.
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 Terbutaline 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 14 days on the web. No card needed.
Other interactions of Terbutaline
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 Terbutaline with Thioridazine?
MediHelp rates the interaction as major. Terbutaline 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 markedly prolongs the QT interval, and terbutaline can cause hypokalemia and tachycardia, both of which increase the risk of torsades de pointes. The combination may result in life-threatening ventricular arrhythmia.
How serious is the interaction between Terbutaline 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 prefer an alternative bronchodilator route such as inhaled therapy at the lowest effective dose. If used, monitor ECG and serum potassium and correct electrolyte disturbances.
What other medicines interact with Terbutaline?
MediHelp also lists interactions of Terbutaline with, for example, Carvedilol, Droperidol, Fexinidazole. The full list is on the Terbutaline 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.
