Drug interactions
Hydrochlorothiazide-valsartan + Quinidine
Severity: Moderate
Hydrochlorothiazide-valsartan and Quinidine: 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
Hydrochlorothiazide can cause hypokalemia and hypomagnesemia, which increase the risk of QT prolongation and torsades de pointes with quinidine. Thiazide-induced urine alkalinization may also reduce quinidine elimination.
What this interaction means in plain words
Hydrochlorothiazide-valsartan and Quinidine 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.
Hydrochlorothiazide-valsartan belongs to Cardiovascular; Quinidine belongs to Anti Parasitic.
Why it happens
Diuretic-induced electrolyte depletion augments quinidine proarrhythmic QT effects, with possible reduced renal quinidine clearance.
What to do
Monitor potassium and magnesium and correct deficits. Obtain an ECG for QT interval and monitor quinidine levels or toxicity.
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?
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Other interactions of Hydrochlorothiazide-valsartan
- Aliskiren + Hydrochlorothiazide-valsartan Contraindicated
- Dofetilide + Hydrochlorothiazide-valsartan Contraindicated
- Hydrochlorothiazide-valsartan + Sparsentan Contraindicated
- Aldesleukin + Hydrochlorothiazide-valsartan Major
- Amifostine + Hydrochlorothiazide-valsartan Major
- Amiloride + Hydrochlorothiazide-valsartan Major
Other interactions of Quinidine
- Adagrasib + Quinidine Contraindicated
- Arsenic trioxide + Quinidine Contraindicated
- Artemether / lumefantrine + Quinidine Contraindicated
- Chloroquine + Quinidine Contraindicated
- Dofetilide + Quinidine Contraindicated
- Dronedarone + Quinidine Contraindicated
Frequently asked questions
Can I take Hydrochlorothiazide-valsartan with Quinidine?
MediHelp rates the interaction as moderate. Hydrochlorothiazide-valsartan and Quinidine 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. Hydrochlorothiazide can cause hypokalemia and hypomagnesemia, which increase the risk of QT prolongation and torsades de pointes with quinidine. Thiazide-induced urine alkalinization may also reduce quinidine elimination.
How serious is the interaction between Hydrochlorothiazide-valsartan and Quinidine?
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 potassium and magnesium and correct deficits. Obtain an ECG for QT interval and monitor quinidine levels or toxicity.
What other medicines interact with Hydrochlorothiazide-valsartan?
MediHelp also lists interactions of Hydrochlorothiazide-valsartan with, for example, Aliskiren, Dofetilide, Sparsentan. The full list is on the Hydrochlorothiazide-valsartan page.
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