pharmacopeia
GET
/api/v1/drug/losartan

Boxed warning

FETAL TOXICITY When pregnancy is detected, discontinue losartan potassium as soon as possible. Drugs that act directly on the renin-angiotensin system can cause injury and death to the developing fetus [see Warnings and Precautions (5.1) ]. WARNING: FETAL TOXICITY See full prescribing information for complete boxed warning. When pregnancy is detected, discontinue losartan potassium as soon as possible. Drugs that act directly on the renin-angiotensin system can cause injury and death to the developing fetus. (5.1)

2D structure
[2-butyl-5-chloro-3-[[4-[2-(2H-tetrazol-5-yl)phenyl]phenyl]methyl]imidazol-4-yl]methanol
SMILES CCCCC1=NC(=C(N1CC2=CC=C(C=C2)C3=CC=CC=C3C4=NNN=N4)CO)Cl
InChIKey PSIFNNKUMBGKDQ-UHFFFAOYSA-N

Mechanism of action

Sourced from openFDA

Angiotensin II [formed from angiotensin I in a reaction catalyzed by angiotensin converting enzyme (ACE, kininase II)] is a potent vasoconstrictor, the primary vasoactive hormone of the renin-angiotensin system, and an important component in the pathophysiology of hypertension. It also stimulates aldosterone secretion by the adrenal cortex.

Angiotensin 2 Receptor

Indications

Sourced from openFDA
  • Losartan potassium tablets are an angiotensin II receptor blocker (ARB) indicated for: • Treatment of hypertension, to lower blood pressure in adults and children greater than 6 years old. Lowering blood pressure reduces the risk of fatal and nonfatal cardiovascular events, primarily strokes and myocardial infarctions.ICD-10: I10

Contraindications

Sourced from openFDA
  • Losartan potassium is contraindicated: • In patients who are hypersensitive to any component of this product. • For coadministration with aliskiren in patients with diabetes.contraindicated

Dosage & administration

Sourced from openFDA

Hypertension • Usual adult dose: 50 mg once daily. (2.1) • Usual pediatric starting dose: 0.7 mg per kg once daily (up to 50 mg). (2.1) Hypertensive Patients with Left Ventricular Hypertrophy • Usual starting dose: 50 mg once daily. (2.2) • Add hydrochlorothiazide 12.5 mg and/or increase losartan potassium to 100 mg followed by an increase to hydrochlorothiazide 25 mg if further blood pressure response is needed. (2.2 , 14.2) Nephropathy in Type 2 Diabetic Patients • Usual dose: 50 mg once daily. (2.3) • Increase dose to 100 mg once daily if further blood pressure response is needed. (2.3) 2.1 Hypertension Adult Hypertension The usual starting dose of losartan potassium tablets is 50 mg once daily. The dosage can be increased to a maximum dose of 100 mg once daily as needed to control blood pressure [see Clinical Studies (14.1) ]. A starting dose of 25 mg is recommended for patients with possible intravascular depletion (e.g., on diuretic therapy). Pediatric Hypertension The usual recommended starting dose is 0.7 mg per kg once daily (up to 50 mg total) administered as a tablet or a suspension [see Dosage and Administration (2.5) ]. Dosage should be adjusted according to blood pressure response. Doses above 1.4 mg per kg (or in excess of 100 mg) daily have not been studied in pediatric patients [see Clinical Pharmacology (12.3) , Clinical Studies (14.1) , and Warnings and Precautions (5.2) ].

Warnings & precautions

Sourced from openFDA

• Hypotension: Correct volume or salt depletion prior to administration of losartan potassium. (5.2) • Monitor renal function and potassium in susceptible patients. (5.3 , 5.4) 5.1 Fetal Toxicity Losartan potassium can cause fetal harm when administered to a pregnant woman. Use of drugs that act on the renin-angiotensin system during the second and third trimesters of pregnancy reduces fetal renal function and increases fetal and neonatal morbidity and death. Resulting oligohydramnios can be associated with fetal lung hypoplasia and skeletal deformations. Potential neonatal adverse effects include skull hypoplasia, anuria, hypotension, renal failure, and death. When pregnancy is detected, discontinue losartan potassium as soon as possible [see Use in Specific Populations (8.1) ]. 5.2 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 losartan potassium. Correct volume or salt depletion prior to administration of losartan potassium [see Dosage and Administration (2.1) ]. 5.3 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.

Adverse reactions

Sourced from openFDA

Most common adverse reactions (incidence ≥2% and greater than placebo) are: dizziness, upper respiratory infection, nasal congestion, and back pain. (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Zydus Pharmaceuticals USA Inc. at 1-877-993-8779 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Hypertension Losartan potassium has been evaluated for safety in more than 3300 adult patients treated for essential hypertension and 4058 patients/subjects overall. Over 1200 patients were treated for over 6 months and more than 800 for over one year. Treatment with losartan potassium was well-tolerated with an overall incidence of adverse events similar to that of placebo. In controlled clinical trials, discontinuation of therapy for adverse events occurred in 2.3% of patients treated with losartan potassium and 3.7% of patients given placebo. In 4 clinical trials involving over 1000 patients on various doses (10 to 150 mg) of losartan potassium and over 300 patients given placebo, the adverse events that occurred in ≥2% of patients treated with losartan potassium and more commonly than placebo were: dizziness (3% vs. 2%), upper respiratory infection (8% vs. 7%), nasal congestion (2% vs. 1%), and back pain (2% vs. 1%).

Use in specific populations

Sourced from openFDA

• Losartan potassium is not recommended in pediatric patients less than 6 years of age or in pediatric patients with glomerular filtration rate less than 30 mL/min/1.73 m 2 . (2.1 , 8.4) • Hepatic Impairment: Recommended starting dose 25 mg once daily. (2.4 , 8.8 , 12.3) 8.1 Pregnancy Risk Summary Losartan potassium can cause fetal harm when administered to a pregnant woman. Use of drugs that act on the renin-angiotensin system during the second and third trimesters of pregnancy reduces fetal renal function and increases fetal and neonatal morbidity and death. 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. When pregnancy is detected, discontinue losartan potassium as soon as possible (see Clinical Considerations). The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.

Pharmacokinetics

Sourced from openFDA
Metabolism
Absorption Following oral administration, losartan is well absorbed and undergoes substantial first-pass metabolism. The systemic bioavailability of losartan is approximately 33%.

Overdosage

Sourced from openFDA

Significant lethality was observed in mice and rats after oral administration of 1000 mg/kg and 2000 mg/kg, respectively, about 44 and 170 times the maximum recommended human dose on a mg/m 2 basis. Limited data are available in regard to overdosage in humans. The most likely manifestation of overdosage would be hypotension and tachycardia; bradycardia could occur from parasympathetic (vagal) stimulation. If symptomatic hypotension should occur, supportive treatment should be instituted. Neither losartan nor its active metabolite can be removed by hemodialysis.

Approval history

Sourced from openFDA
  • Apr 14, 1995NDANDA020386Organon
  • Apr 28, 1995NDANDA020387Organon
  • Apr 6, 2010ANDAANDA077157Teva Pharms
  • May 21, 2010ANDAANDA078245Lupin Ltd
  • Oct 6, 2010ANDAANDA090382Strides Pharma
  • Oct 6, 2010ANDAANDA090083Aurobindo Pharma
  • Oct 6, 2010ANDAANDA090428Alembic Pharms Ltd
  • Mar 13, 2025NDANDA218772Scienture

FAERS reports

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Reference statistics only. FAERS reports are voluntarily submitted and are not incidence rates, safety signals, or causal evidence. Counts reflect reporting volume — how often a reaction was reported, not how often it occurs. For decision-grade use, consult openFDA and the FAERS Public Dashboard directly.
206,971 total reports matchedLatest report Share = reports listing the reaction ÷ total matched reports. Rows can sum to >100% because a single report often lists multiple reactions.
  1. 1Fatigue14,3016.9%
  2. 2Diarrhoea11,9745.8%
  3. 3Nausea11,7525.7%
  4. 4Drug Ineffective11,4995.6%
  5. 5Dyspnoea10,5845.1%
  6. 6Dizziness10,0974.9%
  7. 7Headache9,7014.7%
  8. 8Pain9,0284.4%
  9. 9Off Label Use8,1844.0%
  10. 10Arthralgia7,7143.7%
  11. 11Asthenia7,3853.6%
  12. 12Malaise7,0553.4%
  13. 13Cough6,5653.2%
  14. 14Vomiting6,5633.2%
  15. 15Fall6,5413.2%

Literature

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Recent PubMed references pinned to Losartan as a MeSH major topic. Citations link to pubmed.ncbi.nlm.nih.gov.

Clinical trials

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The 10 most recently updated of 446 ClinicalTrials.gov registrations naming Losartan as an intervention. Registration is not evidence of efficacy or safety — reference crosswalk only.

Structural analogs

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Ranked by 2D fingerprint (Tanimoto) similarity over PubChem structures. Structural proximity only — not a claim of therapeutic equivalence.

Frequently asked questions

How does Losartan work?
Angiotensin II [formed from angiotensin I in a reaction catalyzed by angiotensin converting enzyme (ACE, kininase II)] is a potent vasoconstrictor, the primary vasoactive hormone of the renin-angiotensin system, and an important component in the pathophysiology of hypertension. It also stimulates aldosterone secretion by the adrenal cortex.
What is Losartan used for?
According to FDA labeling, Losartan carries indications including: Losartan potassium tablets are an angiotensin II receptor blocker (ARB) indicated for: • Treatment of hypertension, to lower blood pressure in adults and children greater than 6 years old. Lowering blood pressure reduces the risk of fatal and nonfatal cardiovascular events, primarily strokes and myocardial infarctions.. This is a reference summary of labeled uses, not medical advice or a treatment recommendation.
What class of drug is Losartan?
Losartan is classified as Angiotensin II receptor blockers (ARBs), plain, Angiotensin 2 Receptor Blocker, Angiotensin 2 Receptor Antagonists, Decreased Blood Pressure, Decreased Intravascular Volume, Decreased Mineralocorticoid Secretion, Decreased Renal K+ Excretion, Increased Renal Na+ Excretion, Renal Arterial Vasoconstriction, Renal Arterial Vasodilation.
What are the brand names for Losartan?
Losartan is marketed under brand names including Arbli, Cozaar, Hyzaar.
What are the contraindications for Losartan?
Losartan labeling lists contraindications including: Losartan potassium is contraindicated: • In patients who are hypersensitive to any component of this product. • For coadministration with aliskiren in patients with diabetes.. Always consult the full prescribing information and a clinician.
Note. Data for losartan is illustrative MVP content compiled from public sources. pharmacopeia is for educational and informational use only and is not a substitute for professional medical advice.

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