Angiotensin II antagonists

Antihypertensive therapy.

Losartan

Angiotensin-receptor blocker (ARBs, sartans)

valsartan, candesartan, losartan, irbesartan

same as ACE inhibitors, mostly used as second-line treatment if ACE inhibitors are not tolerated

• Angioedema: can be tried under close surveillance if no adequate alternative is available

• Non-life-threatening side effects (e.g., dry cough ): commonly used

inhibition of angiotensin II receptor type 1 (AT1 receptor)

• ↓ Vasoconstriction → ↓ blood pressure

• ↓ Secretion of aldosterone → ↓ reabsorption of Na+ and water → ↓ blood pressure

• ↑ Renin secretion (compensatory) → ↑ angiotensin I → ↑ angiotensin II

• ↓ Proteinuria and ↓ progression of proteinuric kidney disease

• ↓ Cardiac remodeling after acute myocardial infarction or chronic hypertensive disease

• No bradykinin elevation (opposed to ACE inhibitors)

• Angioedema

• Hyperkalemia

• ↓ GFR (with ↑ creatinine)

• Hypotension

• Teratogenicity

• Leukopenia

• Rash

• Absolute contraindications

  • Hypersensitivity

  • C1 esterase inhibitor deficiency (due to predisposition to angioedema)

  • Pregnancy: risk of harm to the fetus (e.g., renal impairment, renal malformations, oligohydramnios, placental insufficiency)

  • Breastfeeding

• Relative contraindications

  • Aortic stenosis

  • Renal dysfunction, consider altering dose if GFR < 60 mL/min

  • Bilateral renal artery stenosis or a solitary kidney: GFR is already decreased and further reduction may lead to acute kidney injury.

• Other antihypertensive drugs → ↑ hypotensive effect

• NSAIDs → ↓ antihypertensive effect

• Potassium-sparing diuretics or other drugs that increase potassium level: ↑ hyperkalemia

• ↑ Level of lithium due to ↓ renal elimination

• Allopurinol: ↑ risk of immunological reactions or leukopenia