This page contains brief details about the drug , it's indication, dosage & administaration, mechanism of action, related brands with strength, warnings and common side effects.

Background and Date of Approval

Losartan was first approved by the U.S. Food and Drug Administration (FDA) in 1995 for treating hypertension and is scheduled for generic release in April 2010.

Mechanism of Action of undefined

Losartan and its main active metabolite inhibit angiotensin II vasoconstrictor and aldosterone-secreting actions by selectively blocking angiotensin II binding to the AT1 receptor in various tissues (e.g., vascular smooth muscle, adrenal gland). It is a non-competitive inhibitor of AT1 and has an active metabolite 10–40 times more powerful by weight than unmetabolized Losartan. Losartan lowers blood pressure by preventing the binding of angiotensin II, which relaxes the smooth muscles of the blood vessels. Otherwise, angiotensin II would bind to the AT1 receptor, cause vasoconstriction, and increase blood pressure.

Uses of undefined

Losartan helps to treat hypertension (high blood pressure) and diabetic nephropathy and is used to prevent heart failure and stroke. 

undefined Drug administaration and Dosage available

Losartan is available as a tablet with 25mg, 50 mg, and 100 mg. The usual starting dose of Losartan is 50 mg once daily. Take this medication with or without food. Avoid crushing or chewing instead of swallowing it whole.

Warnings, Precautions and Side Effects of undefined


Inform your doctor immediately if you experience allergies to Losartan and its ingredients. Notify your healthcare provider if you are vomiting or having diarrhea. Tell your doctor before the treatment commencement if you are pregnant or having liver, kidney, or heart problems. You might require regular blood pressure monitoring while taking Losartan to avoid fluctuations.


Consult your doctor before using this medication if you are pregnant or plan to have a baby. Discontinue Losartan as soon as possible as it may affect the renin-angiotensin system during the second and third trimesters of pregnancy and can reduce fetal renal dysfunction and even the death of the unborn baby. Avoid breastfeeding your baby while on the medicine as it is unknown if Losartan passes into the breast milk. 

Side Effects

The side effects known to occur commonly during the treatment with Losartan are dizziness, anemia (lack of blood), hyperkalemia (high potassium levels in the blood), orthostatic hypotension (low blood pressure when standing), renal impairment and failure, hypoglycemia (low blood sugar), upper respiratory tract infection, nasal decongestant, back pain, and cough. If you experience severe allergic reactions or heart, liver, and kidney problems, report your physician immediately.

Word Of Advice

Losartan is not recommended for pediatric patients below six years. Monitor renal function and serum potassium periodically as it helps to treat renal impairment and hyperkalemia. It is advised to patients receiving Losartan not to use potassium supplements without consulting their healthcare provider. Losartan is recommended along with a low-salt diet and regular exercise for beneficial results. Driving or using machinery should be avoided if you feel dizzy, tired, or sleepy.

Frequently Asked Question


  1. Edward Chu, Lange’s Basic and clinical pharmacology, Angiotensin receptor blocking agents,14th Edition, 2018, 203-207.
  2. Accord-UK Ltd.., Electronic Medicines Compendium (EMC), [Revised on March 2019] [Accessed on 2nd September 2022]
  3. Merck & co Inc., US Food & Drug Administration, [Revised on Oct 2018]  [Accessed on 2nd September 2022]
  4. Swiss Garnier Life Sciences   [Accessed on 2nd September 2022]


The drug information on this page is not a substitute for medical advice; it is meant for educational purposes only. For further details, consult your doctor about your medical condition to know if you are eligible to receive this treatment.