Adults

For hypertension, the usual starting dose is 50 mg once daily. The dose may be increased to 100 mg once daily if needed. For diabetic nephropathy, the usual starting dose is 50 mg once daily, which may be increased to 100 mg once daily based on blood pressure response.

Elderly

No initial dosage adjustment is typically required, but a lower starting dose (e.g., 25 mg) may be considered for frail or volume-depleted elderly patients.

Renal_impairment

No initial dosage adjustment is generally required for patients with mild to moderate renal impairment. For severe renal impairment or dialysis patients, a lower starting dose (e.g., 25 mg) may be considered.

Onset

Antihypertensive effect begins within 1 hour, with peak effect achieved in 3-6 hours.

Excretion

Approximately 35% of the dose is excreted in urine and 58% in feces, as parent drug and its metabolites.

Half life

Losartan: approximately 2 hours; Active metabolite (E-3174): approximately 6-9 hours.

Absorption

Well absorbed orally, undergoing significant first-pass metabolism to an active carboxylic acid metabolite (E-3174). Bioavailability is approximately 33%. Peak plasma concentrations of Losartan are reached in about 1 hour and for the active metabolite in 3-4 hours.

Metabolism

Extensively metabolized by cytochrome P450 enzymes (CYP2C9 and CYP3A4) in the liver to form the active metabolite E-3174 and other inactive metabolites.

Lithium

Increased serum lithium concentrations and toxicity have been reported.

Aliskiren

Contraindicated in diabetic patients due to increased risk of renal impairment, hypotension, and hyperkalemia.

NSAIDs (Nonsteroidal Anti-inflammatory Drugs)

May reduce the antihypertensive effect of Angilock and increase the risk of renal impairment.

Potassium-sparing diuretics (e.g., Spironolactone) and Potassium supplements

May lead to increased serum potassium levels (hyperkalemia).