Losartan — Angiotensin II receptor blocker (ARB). Study the mechanism, listed uses and warnings from the US label on one sourced card.
Generic name
Losartan
Class
Angiotensin II receptor blocker (ARB)
Mechanism
Losartan and its active metabolite block the vasoconstrictor and aldosterone-secreting effects of angiotensin II at its receptor.
Used for
Hypertension in adults and children aged 6 years and older; Stroke-risk reduction in hypertension with left ventricular hypertrophy; the label reports that this benefit did not apply to Black patients; Diabetic nephropathy with elevated serum creatinine and proteinuria in type 2 diabetes with a history of hypertension
Common side effects
Dizziness; Upper respiratory infection; Nasal congestion; Back pain
Boxed warning
Drugs acting on the renin-angiotensin system can cause fetal injury and death; discontinue when pregnancy is detected.
Warnings
Hypotension in volume-depleted patients; Renal function changes; Hyperkalemia
Interactions
Potassium-raising agents; Lithium; NSAIDs
Brand questions use only name pairings verified against the linked product source. Unverified pairings are withheld from these questions; the other study content remains available.
Label date: 20260827 · For learning, not clinical decisions. US label and brand information; always consult the current source.
Source snapshot checked: 2026-10-21. The source document and selected fields were compared. The complete card has not had an independent clinical review.
Mechanism: Losartan selectively blocks angiotensin II binding at AT1 receptors; hydrochlorothiazide increases renal sodium and chloride excretion.
On both cards: Common side effects — Dizziness; Upper respiratory infection; Back pain · Warnings — Hypotension in volume-depleted patients · Interactions — Potassium-raising agents; Lithium; NSAIDs
Only on the Losartan / Hydrochlorothiazide card: Used for — Hypertension; this fixed-dose combination is not initial therapy except in selected severe cases where prompt control outweighs combination-initiation risk; Stroke-risk reduction in hypertension with left ventricular hypertrophy; the label reports evidence that this specific benefit does not apply to Black patients · Common side effects — Cough · Warnings — Renal function and electrolyte changes; Acute angle-closure glaucoma
Mechanism: Selectively blocks angiotensin II binding to AT1 receptors, inhibiting its vasoconstrictor and aldosterone-secreting effects.
On both cards: Used for — Hypertension in adults and children aged 6 years and older · Common side effects — Dizziness · Interactions — Lithium; NSAIDs
Only on the Valsartan card: Used for — Reduction of heart-failure hospitalization in adults with NYHA class II–IV heart failure; Reduction of cardiovascular mortality in clinically stable adults with left ventricular failure or dysfunction after myocardial infarction · Common side effects — Headache; Fatigue; Hypotension; Hyperkalemia · Warnings — Hypotension; Renal function and potassium changes; No aliskiren in diabetes · Interactions — Potassium-sparing diuretics / supplements
Mechanism: Olmesartan blocks angiotensin II effects, amlodipine blocks calcium entry into vascular smooth muscle, and HCTZ promotes sodium and chloride excretion.
On both cards: Common side effects — Dizziness · Warnings — Hypotension in volume-depleted patients · Interactions — Lithium; NSAIDs
Only on the Olmesartan / Amlodipine / Hydrochlorothiazide card: Used for — Hypertension requiring the selected olmesartan/amlodipine/hydrochlorothiazide combination; not indicated for initial therapy · Common side effects — Peripheral edema; Headache; Fatigue; Muscle spasms · Warnings — Fluid and electrolyte imbalance; Sprue-like enteropathy · Interactions — Aliskiren (in diabetes)
An item counts as shared only when both cards use the same wording. If a card does not list an item, that is not a statement that the effect never occurs.
Boxed warnings on related cards
Losartan / Hydrochlorothiazide: Fetal toxicity: drugs acting on the renin-angiotensin system can injure or kill the developing fetus; stop when pregnancy is detected.
Valsartan: Fetal toxicity: drugs acting on the renin-angiotensin system can injure or kill the developing fetus; stop when pregnancy is detected.
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