Irbepress (Irbesartan)

Irbesartan acts on the renin‑angiotensin‑aldosterone system to control blood pressure and protect renal function.

• Hypertension: lowers elevated blood pressure and reduces cardiovascular risk.
• Diabetic nephropathy: slows progression of kidney damage in patients with type 2 diabetes.
• Heart failure: improves symptoms and reduces hospitalisation in patients with reduced ejection fraction.

• Irbesartan selectively blocks angiotensin II type 1 (AT1) receptors, preventing angiotensin II from inducing vasoconstriction and aldosterone secretion. This antagonism leads to vasodilation, reduced sodium and water retention, and ultimately lower systemic blood pressure while offering renal protective effects.

Adverse reactions may vary in frequency and severity.

Common Side Effects

• Dizziness: sensation of light‑headedness, especially after standing.
• Headache: mild to moderate pain in the head region.
• Fatigue: unusual tiredness or lack of energy.
• Upper respiratory infection: symptoms such as sore throat or nasal congestion.
• Hyperkalemia: elevated blood potassium levels.
• Cough: occasional dry throat irritation.

Serious or Rare Side Effects

• Angioedema: swelling of the face, lips, tongue or throat that may compromise breathing.
• Acute renal failure: sudden loss of kidney function, indicated by reduced urine output.
• Severe hypotension: markedly low blood pressure causing faintness.
• Hepatotoxicity: liver injury presenting with jaundice or elevated enzymes.
• Myocardial infarction: rare occurrence of heart attack.
• Anaphylaxis: severe allergic reaction with rash, itching and breathing difficulty.

Patients should be monitored for specific safety considerations before and during therapy.

• Renal function monitoring: assess serum creatinine and eGFR regularly.
• Serum potassium checks: avoid hyperkalemia, especially when combined with potassium‑sparing agents.
• Pregnancy avoidance: contraindicated in pregnancy due to fetal toxicity.
• Elderly caution: start at lower doses and monitor for orthostatic hypotension.
• Drug‑induced hypotension: advise patients to rise slowly from sitting or lying positions.
• Store at room temperature: keep in the original container, protect from moisture and direct sunlight.

Irbesartan may interact with several drug classes, altering efficacy or safety.

Major Interactions (Avoid)

• Aliskiren (in diabetic patients): increased risk of renal impairment and hyperkalemia.
• Potassium‑sparing diuretics: additive hyperkalemia risk.
• ACE inhibitors: combined use raises angioedema incidence.
• NSAIDs: may diminish antihypertensive effect and impair renal function.
• Lithium: can raise lithium concentrations, leading to toxicity.

Moderate Interactions (Monitor Closely)

• Loop or thiazide diuretics: may enhance hypotensive effect; monitor blood pressure.
• CYP2C9 inhibitors (e.g., fluconazole): may increase irbesartan plasma levels; adjust dose if needed.