Losartan and Quinapril and hydrochlorothiazide interaction
Losartan and Quinapril 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 (COZAAR) label · effective 2026-01-20
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 COZAAR.
NSAIDs: Increased risk of renal impairment and reduced diuretic, natriuretic, and antihypertensive effects.
Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) 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 angiotensin II receptor antagonists (including losartan)…
Dual Blockade of the Renin-Angiotensin System (RAS) Dual blockade of the RAS with angiotensin receptor blockers, ACE inhibitors, or aliskiren is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function (including acute renal failure) compared to monotherapy.
Renal Function Deterioration Changes in renal function including acute renal failure can be caused by drugs that inhibit the renin-angiotensin system and by diuretics.
From the Quinapril and hydrochlorothiazide label · effective 2023-12-11
The thiazide component of quinapril and hydrochlorothiazide tablets may potentiate the action of other antihypertensive drugs, especially ganglionic or peripheral adrenergic- blocking drugs.
Quinapril and hydrochlorothiazide tablets should be used cautiously in patients receiving concomitant therapy with other antihypertensives.
Most epidemiologic studies examining fetal abnormalities after exposure to antihypertensive use in the first trimester have not distinguished drugs affecting the renin-angiotensin system from other antihypertensive agents.
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.