Chlorthalidone and Metolazone interaction
Chlorthalidone and Metolazone: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Metolazone label · effective 2026-01-15
Other Antihypertensive Drugs When metolazone tablets, USP, are used with other antihypertensive drugs, particular care must be taken to avoid excessive reduction of blood pressure, especially during initial therapy.
Dosage adjustments of other antihypertensives may be necessary.
Anticoagulants Metolazone, as well as other thiazide-like diuretics, may affect the hypoprothrombinemic response to anticoagulants; dosage adjustments may be necessary.
Other Antihypertensives When metolazone tablets, USP, are used with other antihypertensive drugs, care must be taken, especially during initial therapy.
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.
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.