Mozartan (Losartan Potassium)

Losartan Potassium is an ARB that lowers blood pressure and protects target organs in several cardiovascular and renal conditions.

• Hypertension: reduces systolic and diastolic pressure, decreasing risk of stroke and myocardial infarction.
• Heart failure: improves symptoms and survival by lowering after‑load.
• Diabetic nephropathy: slows progression of renal impairment in patients with type 2 diabetes.
• Stroke risk reduction in left ventricular hypertrophy: lowers incidence of cerebrovascular events in hypertensive patients with LVH.

• Losartan Potassium selectively blocks angiotensin II type 1 (AT1) receptors, preventing angiotensin II from inducing vasoconstriction, aldosterone release, and sympathetic activation. This antagonism leads to vasodilation, reduced sodium and water retention, and lower blood pressure, thereby mitigating cardiovascular strain and protecting end‑organ function.

Common Side Effects

• Dizziness: feeling light‑headed, especially after standing.
• Headache: mild to moderate intensity.
• Fatigue: general tiredness without exertion.
• Nasal congestion: stuffy or runny nose.
• Upper respiratory infection: mild cold‑like symptoms.

Serious or Rare Side Effects

• Angioedema: swelling of face, lips, tongue, or throat requiring immediate medical attention.
• Hyperkalemia: elevated serum potassium that can cause cardiac arrhythmias.
• Acute renal impairment: sudden decrease in kidney function, especially when combined with other nephrotoxic agents.
• Hepatic injury: abnormal liver enzymes or jaundice.
• Severe hypotension: markedly low blood pressure leading to dizziness or fainting.

Before initiating therapy, clinicians should assess patient-specific factors and monitor relevant parameters.

• Blood pressure monitoring: ensure adequate control and avoid excessive hypotension.
• Renal function assessment: check serum creatinine and eGFR periodically.
• Serum potassium measurement: monitor for hyperkalemia, especially with potassium‑sparing agents.
• Pregnancy avoidance: Losartan is contraindicated in pregnancy due to fetal toxicity.
• Elderly caution: start at lower doses and monitor for orthostatic effects.
• Store at room temperature: keep in the original container, protect from moisture and direct sunlight.

Losartan may interact with several medicines, requiring dose adjustments or avoidance.

Major Interactions (Avoid)

• Aliskiren in diabetic patients: increased risk of renal dysfunction and hyperkalemia.
• Concurrent ACE inhibitors or other ARBs: additive effect on potassium and renal function.
• Potassium‑sparing diuretics (e.g., spironolactone): heightened hyperkalemia risk.
• NSAIDs (e.g., ibuprofen): may blunt antihypertensive effect and impair renal perfusion.

Moderate Interactions (Monitor Closely)

• Loop or thiazide diuretics: may enhance hypotensive response.
• Lithium: losartan can raise lithium levels, risking toxicity.
• CYP2C9 inhibitors (e.g., fluconazole): may increase losartan plasma concentrations.
• Rifampin: may reduce losartan effectiveness by inducing metabolism.