Metro Drug
Full Prescribing Info
Losartan potassium.
Each film-coated tablet contains: Losartan potassium 50 mg or 100 mg.
Pharmacology: Pharmacokinetics: Losartan potassium is an angiotensin II receptor antagonist with antihypertensive activity due mainly to selective blockage of AT1, receptors and the consequent reduced pressure effect on angiotensin II.
Losartan potassium is readily absorbed from the gastrointestinal tract following oral administration, with an oral bioavailability of about 33%. It undergoes first-pass metabolism to form an active carboxylic acid metabolite E-3174 (EXP-3174), which has greater pharmacological activity than Losartan and some inactive metabolites. Metabolism is primarily by cytochrome P450 isoenzyme CYP2C9 and CYP3A4. Peak plasma concentrations of Losartan and E-3174 occur about 1 hour and 3 to 4 hours respectively, after an oral dose. Both Losartan and E-3174 are more than 98% bound to plasma proteins. Losartan is excreted in the urine and in the feces via bile, as unchanged drug and metabolites. Following oral dosing, about 35% of the dose is excreted in the urine, and about 60% in the feces. The terminal elimination half-lives of Losartan and E-3174 are about 1.5 to 2.5 hours and 3 to 9 hours respectively.
Losartan potassium is used in the management of hypertension and may have role in patients who develop cough with ACE inhibitors. Management of diabetic nephropathy.
Dosage/Direction for Use
Usual dose: 50 mg once daily.
This dose may be increased if necessary to 100 mg daily as a single dose or in two divided doses. An initial dose of 25 mg once daily may be used in the elderly over 76 years, and for patients with moderate to severe renal impairment (creatinine clearance less than 20 mL per minute) or intravascular fluid depletion.
Or as prescribed by a physician.
Regarding the overdosage there are limited data available. The most likely sign and symptoms of overdosage would be hypotension and tachycardia; bradycardia may occur from parasympathetic (vagal) stimulation. If symptomatic hypotension occur, the supportive treatment should be made.
Losartan potassium is contraindicated in pregnancy. Hypersensitivity.
Should be discontinued when pregnancy is diagnosed.
Special Precautions
Losartan potassium should be used with care, if at all, during breast feeding. It should be used with caution in patients with renal artery stenosis. Reduced doses may be required in patients with renal or hepatic impairment. Patients with volume depletion may experience hypotension.
Vulnerable Group: No dosage adjustment needed for renal failure and elderly. Decrease the dosage in hepatic insufficiencies. Medication error.
Use In Pregnancy & Lactation
Losartan potassium is contraindicated in pregnancy. Should be discontinued when pregnancy is diagnosed.
Losartan potassium should be used with care, if at all, during breast feeding.
Adverse Reactions
Adverse effects include dizziness, headache and dose-related orthostatic hypotension. Hypotension may occur particularly in patients with volume depletion (for example those who have received high-dose diuretics). Losartan potassium may cause hyperkalemia in patients with renal disease. Other adverse effects that have been reported with angiotensin II receptor antagonist include respiratory tract disorder, back pain, gastrointestinal disturbances, fatigue, neutropenia, hypotension, impaired renal function, rash, pruritus, angioedema, urticaria, elevated liver enzyme, myalgia and fatigue.
Drug Interactions
The antihypertensive effects of losartan may be potentiated by drugs or other agents that lower blood pressure. An additive hyperkalemic effect is possible: supplements, potassium-sparing diuretics or other drugs that can cause hyperkalemia; losartan and potassium-sparing diuretics should not generally be given together. NSAIDs should be used with caution in patients taking losartan as the risk of renal impairment may be increased, particularly in those who are adequately hydrated; use of NSAIDs may also attribute to hypotensive effect of losartan. Losartan and some other angiotensin II receptor antagonist are metabolized by cytochrome P450 isoenzymes and interactions may occur with drugs that affect these enzymes.
Store at temperatures not exceeding 30°C.
ATC Classification
C09CA01 - losartan ; Belongs to the class of angiotensin II receptor blockers (ARBs). Used in the treatment of cardiovascular disease.
FC tab 50 mg (white to off-white, oblong, biconvex, plain on both sides) x 30's. 100 mg (white to off-white, oval, biconvex, plain on both sides) x 30's.
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