Losartan potassium
[CAS# 124750-99-8]

Identification

• Classification: API >> Circulatory system medication >> Antihypertensive drug
• Name: Losartan potassium
• Synonyms: 2-Butyl-4-chloro-1-[[2'-(1H-tetrazol-5-yl)[1,1'-biphenyl]-4-yl]methyl]-1H-imidazole-5-methanol monopotassium salt
• Molecular Formula: C₂₂H₂₂CIKN₆OK
• Molecular Weight: 461.01
• CAS Registry Number: 124750-99-8
• EC Number: 627-032-3
• SMILES: CCCCC1=NC(=C(N1CC2=CC=C(C=C2)C3=CC=CC=C3C4=NN=N[N-]4)CO)Cl.[K+]

Safety Data

• Hazard Symbols: GHS02;GHS07 Danger
• Risk Statements: H228-H315-H319
• Safety Statements: P240-P210-P241-P264-P280-P302+P352-P370+P378-P337+P313-P305+P351+P338-P362+P364-P332+P313

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Reproductive toxicity	Repr.	1B	H360
Serious eye damage	Eye Dam.	1	H318
Reproductive toxicity	Lact.	-	H362
Specific target organ toxicity - repeated exposure	STOT RE	2	H373
Skin sensitization	Skin Sens.	1	H317
Reproductive toxicity	Repr.	1B	H360D
Reproductive toxicity	Repr.	2	H361
Eye irritation	Eye Irrit.	2	H319
Specific target organ toxicity - single exposure	STOT SE	3	H335
Skin irritation	Skin Irrit.	2	H315
Acute toxicity	Acute Tox.	4	H332
Reproductive toxicity	Repr.	2	H360
Skin sensitization	Skin Sens.	1B	H317

Discovery and Applications

Losartan potassium, a medication used to treat high blood pressure (hypertension) and heart failure, was discovered in the late 1980s by researchers at Merck & Co. The discovery was part of efforts to develop angiotensin II receptor antagonists, a new class of drugs for hypertension treatment. Losartan works by selectively blocking the angiotensin II receptor subtype AT1, thus preventing its vasoconstrictive and aldosterone-secreting effects. This discovery marked a significant advancement in cardiovascular medicine, offering an alternative to traditional antihypertensive medications like ACE inhibitors. Losartan potassium was approved by the U.S. Food and Drug Administration (FDA) in 1995 and has since become one of the most widely prescribed antihypertensive drugs worldwide.

Losartan potassium is primarily used for the management of hypertension, either alone or in combination with other antihypertensive medications. By blocking the effects of angiotensin II, losartan dilates blood vessels, reducing blood pressure and lowering the risk of cardiovascular events such as stroke and heart attack.

In addition to hypertension, losartan potassium is indicated for the treatment of heart failure with reduced ejection fraction (HFrEF). It helps improve symptoms and reduce the risk of hospitalization and mortality in patients with heart failure by inhibiting the harmful effects of angiotensin II on the heart and blood vessels. Losartan's ability to decrease afterload and preload contributes to its beneficial effects on cardiac function and remodeling in heart failure patients.

Losartan potassium is also used to slow the progression of diabetic nephropathy, a common complication of diabetes characterized by kidney damage and impaired kidney function. It exerts renoprotective effects by reducing intraglomerular pressure and proteinuria, thus preserving kidney function and delaying the onset of end-stage renal disease in diabetic patients.

Losartan potassium has shown promise in preventing stroke, particularly in patients with hypertension and left ventricular hypertrophy (LVH). By lowering blood pressure and reducing cardiac workload, losartan decreases the risk of stroke associated with hypertension and LVH.

Beyond its approved indications, losartan potassium is sometimes used off-label for various conditions, including Marfan syndrome, aortic aneurysm, and migraine prevention. Its ability to block the effects of angiotensin II may have beneficial effects on vascular function and migraine pathophysiology.

References

1998. Effects of combination therapy with enalapril and losartan on the rate of progression of renal injury in rats with 5/6 renal mass ablation. Journal of the American Society of Nephrology : JASN.
DOI: 10.1681/asn.v92224

1997. Simple high-performance liquid chromatographic method for determination of losartan and E-3174 metabolite in human plasma, urine and dialysate. Journal of Chromatography. B, Biomedical Sciences and Applications.
DOI: 10.1016/s0378-4347(97)00489-1

2001. Management of Hypertension. Preventive Cardiology.
DOI: 10.1007/978-1-59259-001-8_6