Losartan and hydrochlorothiazide and Spironolactone and hydrochlorothiazide interaction
Losartan and hydrochlorothiazide 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 Losartan and hydrochlorothiazide (HYZAAR) label · effective 2025-11-26
Hypotension in Volume- or Salt-Depleted Patients In patients with an activated renin-angiotensin system, such as volume- or salt-depleted patients (e.g., those being treated with high doses of diuretics), symptomatic hypotension may occur after initiation of treatment with HYZAAR.
Because losartan decreases uric acid, losartan in combination with hydrochlorothiazide attenuates the diuretic-induced hyperuricemia.
Non-Steroidal Anti-Inflammatory Drugs (NSAIDs): increased risk of renal impairment and reduced diuretic, natriuretic, and antihypertensive effects.
Lithium Increases in serum lithium concentrations and lithium toxicity have been reported with concomitant use of angiotensin II receptor antagonists or thiazide diuretics.
Non-Steroidal Anti-Inflammatory Agents Including Selective Cyclooxygenase-2 Inhibitors Losartan Potassium 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 angiotensin II receptor antagonists (including losartan) may result…
From the Spironolactone and hydrochlorothiazide label · effective 2026-02-10
…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 • other drugs…
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.
Other Metabolic Disturbances Hydrochlorothiazide may alter glucose tolerance and raise serum levels of cholesterol and triglycerides.
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.