Hydrochlorothiazide/Losartan and Losartan Interaction

Drug interaction information between Hydrochlorothiazide/Losartan and Losartan.

Hydrochlorothiazide/Losartan and Losartan have a documented minor interaction in FDA labeling.

FDA drug labeling documents a minor-severity interaction between Hydrochlorothiazide/Losartan and Losartan. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.

Drug A

Hydrochlorothiazide/Losartan

Thiazide Diuretic / ARB Combination

Drug B

Losartan

Angiotensin II Receptor Blocker (ARB)

How They Interact

Taking these medications together can cause your potassium levels to become dangerously high or lead to kidney problems.

FDA Label Information

( 7.5 ) 7.1 Agents Increasing Serum Potassium Coadministration of losartan with other drugs that raise serum potassium levels may result in hyperkalemia. 7.3 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 in deterioration of renal function, including possible acute renal...

Frequently Asked Questions

What SPL severity band is on file for Hydrochlorothiazide/Losartan + Losartan?

Compiled FDA labeling labels this pair minor. That is a source-record field, not an individual medication-combination decision.

Which drug in this pair has the larger labeled-interaction portfolio?

Losartan has 10 labeled pairs on file vs Hydrochlorothiazide/Losartan's 7. In the minor band specifically: Hydrochlorothiazide/Losartan has 5 (also Lisinopril, Hydrochlorothiazide, Cholestyramine, Colestipol); Losartan has 8 (also Fluconazole, Glecaprevir/Pibrentasvir, Hydrochlorothiazide, Hydrochlorothiazide).

What mechanism field is on file for Hydrochlorothiazide/Losartan and Losartan?

Taking these medications together can cause your potassium levels to become dangerously high or lead to kidney problems.

Losartan's labeled portfolio outnumbers Hydrochlorothiazide/Losartan

SPL source-record counts only. This page's band is minor · classes on file: Hydrochlorothiazide/Losartan (Thiazide Diuretic / ARB Combination); Losartan (Angiotensin II Receptor Blocker (ARB)).

Hydrochlorothiazide/Losartan

1 major · 1 moderate · 5 minor · 7 total

Losartan

1 major · 1 moderate · 8 minor · 10 total

Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.