Drug interactions
Chlorthalidone + Lily of the valley
Severity: Major
Chlorthalidone and Lily of the valley: 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
Lily of the valley contains cardiac glycosides with digoxin-like activity. Potassium and magnesium depletion from chlorthalidone sensitizes the heart to glycoside toxicity and increases the risk of dangerous arrhythmias.
What this interaction means in plain words
Chlorthalidone and Lily of the valley 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.
Why it happens
Diuretic-induced hypokalemia and hypomagnesemia enhance myocardial sensitivity to cardiac glycoside effects.
What to do
Avoid use of lily of the valley preparations. If exposure occurs, check potassium, magnesium and ECG and correct electrolyte abnormalities 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?
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Other interactions of Chlorthalidone
Frequently asked questions
Can I take Chlorthalidone with Lily of the valley?
MediHelp rates the interaction as major. Chlorthalidone and Lily of the valley 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. Lily of the valley contains cardiac glycosides with digoxin-like activity. Potassium and magnesium depletion from chlorthalidone sensitizes the heart to glycoside toxicity and increases the risk of dangerous arrhythmias.
How serious is the interaction between Chlorthalidone and Lily of the valley?
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 use of lily of the valley preparations. If exposure occurs, check potassium, magnesium and ECG and correct electrolyte abnormalities promptly.
What other medicines interact with Chlorthalidone?
MediHelp also lists interactions of Chlorthalidone with, for example, Amifostine, Atenolol-chlorthalidone, Candesartan-hydrochlorothiazide. The full list is on the Chlorthalidone page.
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