Cozaar (losartan potassium) is an angiotensin II receptor blocker (ARB) prescribed for the management of hypertension. It works by blocking the action of certain natural substances that tighten blood vessels, allowing blood to flow more smoothly and the heart to pump more efficiently. This medication is also indicated for the treatment of diabetic nephropathy in patients with type 2 diabetes and hypertension, offering a dual protective effect on both cardiovascular and renal systems. Its well-established efficacy and favorable tolerability profile have made it a cornerstone therapy in clinical practice for appropriate patient populations.

Features

• Active ingredient: Losartan Potassium
• Drug class: Angiotensin II Receptor Blocker (ARB)
• Available in tablet form: 25 mg, 50 mg, 100 mg
• Once-daily dosing regimen for hypertension
• Proven nephroprotective effects in type 2 diabetes with proteinuria
• Hepatic metabolism via cytochrome P450 isoenzymes (primarily CYP2C9 and CYP3A4)

Benefits

• Effectively lowers high blood pressure, reducing the strain on the heart and arterial system.
• Significantly slows the progression of kidney disease in patients with type 2 diabetes and elevated proteinuria.
• Demonstrates a lower incidence of dry cough compared to ACE inhibitors, improving treatment adherence.
• Provides 24-hour hemodynamic coverage with a single daily dose, supporting consistent blood pressure control.
• Offers cardiovascular risk reduction by managing hypertension, a major modifiable risk factor.
• Well-tolerated in most patient populations, with a side effect profile often comparable to placebo.

Common use

Cozaar is primarily indicated for the treatment of hypertension, either as monotherapy or in combination with other antihypertensive agents such as diuretics. It is also approved for the reduction of renal disease progression in patients with type 2 diabetes and a history of hypertension, manifested by elevated serum creatinine and proteinuria (>300 mg/day). In some clinical contexts, it may be used off-label for heart failure management when ACE inhibitors are not tolerated, though this is not an FDA-approved indication. Its use is widespread in adult populations, including the elderly, with dosage adjustments based on renal function and therapeutic response.

Dosage and direction

The recommended initial dose for hypertension is 50 mg once daily. The dosage can be increased to 100 mg once daily based on blood pressure response. For volume-depleted patients (e.g., those treated with high-dose diuretics), a starting dose of 25 mg is recommended. In the treatment of 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. Cozaar may be administered with or without food. Tablets should be swallowed whole with a glass of water. Dosage adjustment is necessary in patients with hepatic impairment or a history of renal artery stenosis.

Precautions

Patients should be monitored for hypotension, especially after initiation or dosage increase. Renal function and serum potassium should be assessed periodically, particularly in patients with pre-existing renal impairment, diabetes, or those using potassium supplements or potassium-sparing diuretics. Use with caution in patients with hepatic impairment, as losartan pharmacokinetics may be altered. Cozaar should not be used during pregnancy due to the risk of fetal injury and death; pregnancy should be excluded before initiation and avoided during therapy. Angioedema has been reported with ARBs; discontinue immediately if it occurs. Avoid use in patients with bilateral renal artery stenosis or solitary kidney stenosis.

Contraindications

Cozaar is contraindicated in patients with known hypersensitivity to losartan or any component of the formulation. It is also contraindicated during the second and third trimesters of pregnancy due to the risk of causing fetal harm, including hypotension, neonatal skull hypoplasia, anuria, reversible or irreversible renal failure, and death. Concomitant use with aliskiren in patients with diabetes is contraindicated. It should not be administered to patients with a history of angioedema related to previous ARB or ACE inhibitor therapy.

Possible side effect

Common adverse reactions (≥1% and greater than placebo) include dizziness, upper respiratory infection, nasal congestion, back pain, and fatigue. Less frequently, hypotension, hyperkalemia, and elevated liver enzymes may occur. Postmarketing reports include rare instances of angioedema (including laryngeal edema), rhabdomyolysis, hepatitis, thrombocytopenia, and vasculitis. Most side effects are mild and transient, often resolving with continued therapy. Patients should report any signs of infection, unexplained muscle pain, or swelling of the face/lips/throat promptly.

Drug interaction

Cozaar may increase serum lithium concentrations; monitor lithium levels closely. Concomitant use with NSAIDs may reduce the antihypertensive effect and increase the risk of renal impairment. Potassium-sparing diuretics, potassium supplements, or salt substitutes containing potassium may increase the risk of hyperkalemia. Rifampin may decrease losartan plasma concentrations. CYP2C9 inhibitors (e.g., fluconazole) may increase losartan levels. Use with aliskiren is contraindicated in diabetic patients due to increased risk of renal impairment, hyperkalemia, and hypotension.

Missed dose

If a dose is missed, it should be taken as soon as remembered on the same day. If it is nearly time for the next dose, the missed dose should be skipped, and the regular dosing schedule resumed. Doubling the dose to make up for a missed one is not recommended, as it may increase the risk of hypotension or other adverse effects. Patients should be advised to maintain a consistent dosing routine, ideally taking the medication at the same time each day to ensure stable plasma concentrations.

Overdose

Symptoms of overdose may include hypotension and tachycardia; bradycardia could occur due to vagal stimulation. Management involves supportive care, including intravenous fluids and vasopressors if necessary to maintain blood pressure. Losartan and its active metabolite are not removed by hemodialysis. Gastric lavage and activated charcoal may be considered if ingestion was recent. Close monitoring of vital signs, electrolyte balance, and renal function is essential. There is no specific antidote for losartan overdose.

Storage

Store at controlled room temperature, 20°C to 25°C (68°F to 77°F), with excursions permitted between 15°C and 30°C (59°F and 86°F). Keep in the original container, tightly closed, and protect from light and moisture. Do not store in the bathroom or near sinks. Keep out of reach of children and pets. Do not use beyond the expiration date printed on the packaging. Properly discard any unused or expired medication via a drug take-back program or following FDA-recommended disposal methods.

Disclaimer

This information is intended for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting, changing, or stopping any medication. The prescribing physician should determine the appropriate therapy based on individual patient factors. Not all uses, precautions, or interactions may be listed here. Full prescribing information should be reviewed before administration.

Reviews

Clinical trials and postmarketing surveillance demonstrate Cozaar’s consistent efficacy in blood pressure reduction and renal protection. Many patients report satisfactory control of hypertension with minimal side effects. Some note improved quality of life due to once-daily dosing and absence of cough compared to ACE inhibitors. A subset of users may experience dizziness or fatigue initially, which often subsides. Healthcare providers frequently regard it as a reliable first-line or alternative agent in hypertensive and diabetic renal disease management. Long-term studies support its sustained benefits in cardiovascular and renal outcomes.