Drug interactions
Enalapril-hydrochlorothiazide + Thioridazine
Severity: Moderate
Enalapril-hydrochlorothiazide and Thioridazine: moderate 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 has alpha-blocking properties that can add to the blood pressure lowering of enalapril and hydrochlorothiazide, causing orthostatic hypotension. In addition, thiazide-induced hypokalemia or hypomagnesemia increases the risk of thioridazine-related QT prolongation and torsades de pointes.
What this interaction means in plain words
Enalapril-hydrochlorothiazide and Thioridazine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Enalapril-hydrochlorothiazide belongs to Cardiovascular; Thioridazine belongs to Central Nervous System.
Why it happens
Additive hypotensive effects via alpha-adrenergic blockade, and diuretic-induced electrolyte loss that potentiates thioridazine QT prolongation.
What to do
Monitor blood pressure and orthostatic symptoms, and check potassium and magnesium regularly with correction of deficits. Obtain an ECG if risk factors for QT prolongation are present.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Enalapril-hydrochlorothiazide 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 Enalapril-hydrochlorothiazide
- Aliskiren + Enalapril-hydrochlorothiazide Contraindicated
- Dofetilide + Enalapril-hydrochlorothiazide Contraindicated
- Enalapril-hydrochlorothiazide + Protein a column Contraindicated
- Enalapril-hydrochlorothiazide + Sacubitril / valsartan Contraindicated
- Amifostine + Enalapril-hydrochlorothiazide Major
- Amiloride + Enalapril-hydrochlorothiazide Major
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 Enalapril-hydrochlorothiazide with Thioridazine?
MediHelp rates the interaction as moderate. Enalapril-hydrochlorothiazide and Thioridazine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Thioridazine has alpha-blocking properties that can add to the blood pressure lowering of enalapril and hydrochlorothiazide, causing orthostatic hypotension. In addition, thiazide-induced hypokalemia or hypomagnesemia increases the risk of thioridazine-related QT prolongation and torsades de pointes.
How serious is the interaction between Enalapril-hydrochlorothiazide and Thioridazine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor blood pressure and orthostatic symptoms, and check potassium and magnesium regularly with correction of deficits. Obtain an ECG if risk factors for QT prolongation are present.
What other medicines interact with Enalapril-hydrochlorothiazide?
MediHelp also lists interactions of Enalapril-hydrochlorothiazide with, for example, Aliskiren, Dofetilide, Protein a column. The full list is on the Enalapril-hydrochlorothiazide 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.
