Losartan potassium is the first orally active angiotensin-II receptor (type-AT1) antagonist. Angiotensin-II is a potent vasoconstrictor, which is the primary vasoactive hormone of the renin-angiotensin system and an important component in the pathophysiology of hypertension. Losartan and its principal active metabolite block the vasoconstrictor and aldosterone secreting effects of angiotensin-II to the AT1 receptor. Osartan is now regarded as the first choice therapy for treating high blood pressure.


    Osartan 25 Tablet : Each film coated tablet contains Losartan potassium INN 25 mg.
    Osartan 50 Tablet : Each film coated tablet contains Losartan potassium INN 50 mg.


    Hypertension (including to reduce the risk of stroke in patients with left ventricular hypertrophy), diabetic nephropathy in type 2 diabetes mellitus.

Dosage & Administration

    Usually 50 mg once daily (intravascular volume depletion, initially 25 mg once daily); if necessary increased after several weeks to 100 mg once daily; Elderly over 75 years initially 25 mg daily.


    Osartan is contraindicated in pregnancy and lactation. It is also contraindicated to patients who are hypersensitive to Losartan Potassium or any component of this product.

Warning & Precautions

    Osartan should be used with caution in patients with known hypersensitivity to drugs that act through renin-angiotensin system. A lower dose should be considered when it is administered to the patients with hepatic impairment. Safety and effectiveness of Osartan in paediatric patients have not been established.

Side effects

    In general, treatment with Osartan is well tolerated. The overall incidence of adverse effects reported with Losartan potassium is similar to placebo. The usual adverse events are respiratory infection, dizziness and leg pain.

Drug interaction

    No drug interactions of clinical significance have been identified. Compounds which have been studied in clinical pharmacokinetic trials include hydrochlorothiazide, digoxin, warfarin, cimetidine, ketoconazole and phenobarbital.

Use in special groups

    Use in pregnancy: Osartan must be discontinued as soon as possible when pregnancy is detected.
    Use in lactation: It should not be prescribed during lactation as there is no information in human on the passage of Osartan into breast milk.


    Osartan-25 Tablet: Box containing 60's tablets in blister pack.
    Osartan-50 Tablet: Box containing 30's tablets in blister pack.