Captopril and Spironolactone and hydrochlorothiazide interaction
Captopril and Spironolactone and hydrochlorothiazide: 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 Captopril label · effective 2026-02-06
Hypotension Excessive hypotension was rarely seen in hypertensive patients but is a possible consequence of captopril use in salt/volume depleted persons (such as those treated vigorously with diuretics), patients with heart failure or those patients undergoing renal dialysis.
Patients should be followed closely for the first two weeks of treatment and whenever the dose of captopril and/or diuretic is increased.
In patients with heart failure, reducing the dose of diuretic, if feasible, may minimize the fall in blood pressure.
Non-Steroidal Anti-Inflammatory Agents including Selective Cyclooxygenase – 2 Inhibitors (COX-2 Inhibitors): In patients who are elderly, volume-depleted (including those on diuretic therapy), or with compromised renal function, coadministration of NSAIDs, including selective COX-2 inhibitors, with ACE inhibitors, including captopril, may result in deterioration…
Hypotension—Patients on Diuretic Therapy: Patients on diuretics and especially those in whom diuretic therapy was recently instituted, as well as those on severe dietary salt restriction or dialysis, may occasionally experience a precipitous reduction of blood pressure usually within the first hour after receiving the initial dose of captopril.
From the Spironolactone and hydrochlorothiazide label · effective 2026-02-10
…administration of spironolactone and hydrochlorothiazide tablets with the following drugs or potassium sources may lead to severe hyperkalemia: • other potassium-sparing diuretics • ACE inhibitors • angiotensin II receptor antagonists • aldosterone blockers • non-steroidal anti-inflammatory drugs (NSAIDs), e.g., indomethacin • heparin and low molecular weight heparin…
Spironolactone, when used with ACE inhibitors or indomethacin, even in the presence of a diuretic, has been associated with severe hyperkalemia.
Thiazides may add to or potentiate the action of other antihypertensive drugs.
Drug interactions ACE inhibitors, Angiotensin II receptor antagonists, aldosterone blockers, potassium supplements, heparin, low molecular weight heparin, and other drugs known to cause hyperkalemia: Concomitant administration may lead to severe 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.