| Recommended Dose and Dosage Regimen | The recommended starting dose of losartan for hypertension in adults is usually 50 mg once daily. The dosage may be titrated based on blood pressure response, with a maximum dose of 100 mg once daily. For patients with hypertension and left ventricular hypertrophy, the initial dose may be 50 mg once daily, titrated to 100 mg once daily if needed. For the treatment of diabetic nephropathy in type 2 diabetes, the starting dose is typically 50 mg once daily, titrated to 100 mg once daily based on renal function and blood pressure response. Follow your healthcare provider’s instructions regarding dosing. |
| Frequency of Administration | Losartan is typically administered once daily. |
| Route of Administration | Losartan is administered orally in the form of tablets. |
| Mechanism of Action (MOA) | Losartan is an angiotensin II receptor blocker (ARB) that selectively antagonizes the angiotensin II type 1 (AT1) receptor. By blocking the effects of angiotensin II, losartan dilates blood vessels, reduces peripheral resistance, and decreases aldosterone secretion, leading to decreased blood pressure. |
| Pharmacokinetics (PK) | Losartan is well absorbed after oral administration, with peak plasma concentrations achieved within 1-2 hours. It undergoes extensive first-pass metabolism in the liver to its active metabolite, E-3174. The elimination half-life of losartan is about 1.5-2 hours, while that of its active metabolite is longer (6-9 hours). |
| Pharmacodynamics (PD) | Losartan exerts its pharmacodynamic effects by selectively blocking the binding of angiotensin II to AT1 receptors, thereby inhibiting its vasoconstrictor and aldosterone-secreting actions. This leads to vasodilation, decreased peripheral resistance, and reduced blood pressure. Losartan also attenuates the pathophysiological effects of angiotensin II on cardiac remodeling and renal function. |
| Pathophysiology | Losartan is indicated for the treatment of hypertension and for reducing the risk of stroke in patients with hypertension and left ventricular hypertrophy. It is also used for the treatment of diabetic nephropathy in patients with type 2 diabetes and hypertension. |
| Primary Indications | Hypertension, reduction of stroke risk in hypertensive patients with left ventricular hypertrophy, diabetic nephropathy in patients with type 2 diabetes and hypertension. |
| Contraindications | Contraindications to losartan use include hypersensitivity to losartan or its components, pregnancy (especially in the second and third trimesters), and concomitant use of aliskiren in patients with diabetes. Use caution in patients with bilateral renal artery stenosis, renal impairment, and hepatic impairment. |
| Purpose of Taking Medication | The purpose of losartan therapy is to lower blood pressure, reduce the risk of stroke, and slow the progression of renal disease in patients with hypertension, left ventricular hypertrophy, and diabetic nephropathy. |
| Usage Instructions | Take losartan exactly as prescribed by your healthcare provider. It may be taken with or without food. Swallow the tablet whole with a glass of water. Do not stop taking losartan without consulting your doctor. |
| Precautions and Care | Patients taking losartan should be monitored regularly for blood pressure control, renal function, and electrolyte levels. Advise patients to report any signs of hypotension, hyperkalemia, or renal dysfunction promptly. Dosage adjustments may be necessary in patients with renal impairment. |
| Dietary Considerations | There are no specific dietary restrictions associated with losartan use. However, patients should maintain a healthy diet low in sodium and saturated fats to complement treatment and help control blood pressure. |
| Missed Dose | If a dose of losartan is missed, take it as soon as you remember, unless it is almost time for your next dose. Do not double the dose to catch up. |
| Possible Side Effects | Common side effects of losartan may include dizziness, hypotension, hyperkalemia, fatigue, and upper respiratory tract infections. Rare but serious side effects may include angioedema, renal impairment, and hepatic dysfunction. |
| Storage and Disposal | Store losartan tablets at room temperature away from moisture and heat. Keep the medication in its original packaging and out of reach of children and pets. Dispose of unused or expired medication according to local regulations. |
| Overdose or Emergency | In case of overdose, seek emergency medical attention or contact a poison control center immediately. Management may include supportive care and monitoring of vital signs and electrolyte levels. |
| Monitoring and Laboratory Tests | Patients taking losartan may require regular monitoring of blood pressure, renal function (serum creatinine), potassium levels, and electrolytes. Additional laboratory tests may be performed based on individual clinical needs and risk factors. |
