Chlorthalidone and Lisinopril interaction
Chlorthalidone and Lisinopril: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Chlorthalidone (Thalitone) label · effective 2026-06-25
Effect of chlorthalidone on other drugs Chlorthalidone may add to or potentiate the action of other antihypertensive drugs.
From the Lisinopril (Zestril) label · effective 2025-01-02
Patients at risk of excessive hypotension include those with the following conditions or characteristics: heart failure with systolic blood pressure below 100 mmHg, ischemic heart disease, cerebrovascular disease, hyponatremia, high dose diuretic therapy, renal dialysis, or severe volume and/or salt depletion of any etiology.
In these patients, Zestril should be started under very close medical supervision and such patients should be followed closely for the first two weeks of treatment and whenever the dose of Zestril and/or diuretic is increased.
Risk factors for the development of hyperkalemia include renal insufficiency, diabetes mellitus, and the concomitant use of potassium-sparing diuretics, potassium supplements and/or potassium-containing salt substitutes [see Drug Interactions (7.1) ] .
Diuretics Initiation of Zestril in patients on diuretics may result in excessive reduction of blood pressure.
Potassium-sparing diuretics (spironolactone, amiloride, triamterene, and others) can increase the risk of hyperkalemia.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.