Irbesartan Tarbis (Irbesartan)

Irbesartan is an angiotensin II receptor blocker used to treat conditions related to the renin‑angiotensin system.

• Hypertension: provides sustained blood pressure reduction, helping to lower the risk of stroke, myocardial infarction and other cardiovascular events.
• Diabetic nephropathy: slows the decline of renal function and reduces albuminuria in patients with type 2 diabetes and established kidney disease.
• Heart failure: improves left ventricular function and decreases symptoms such as dyspnea, contributing to reduced hospital admissions in systolic heart failure.

• Irbesartan selectively blocks the binding of angiotensin II to the AT1 receptor on vascular smooth‑muscle cells, adrenal gland and kidney. By preventing this interaction, it inhibits vasoconstriction, aldosterone release and sympathetic activation, leading to vasodilation, reduced sodium and water retention, and lower systemic blood pressure. The effect is dose‑dependent and persists for the duration of the dosing interval, providing consistent blood pressure control.

Irbesartan may be associated with a range of adverse reactions, varying from mild to serious.

Common Side Effects

• Dizziness: feeling of light‑headedness, especially after standing.
• Headache: mild to moderate intensity.
• Fatigue: general tiredness.
• Upper respiratory tract infection: nasopharyngitis symptoms.

Serious or Rare Side Effects

• Hyperkalemia: elevated blood potassium that can cause cardiac arrhythmias.
• Angioedema: swelling of face, lips, tongue or airway requiring emergency care.
• Renal impairment: sudden decrease in kidney function, especially in patients with pre‑existing renal disease.

When prescribing Irbesartan, clinicians should consider several precautionary measures to ensure patient safety.

• Renal function monitoring: assess serum creatinine and eGFR before initiation and periodically during therapy.
• Electrolyte assessment: check serum potassium levels, particularly in patients receiving potassium‑sparing diuretics or supplements.
• Concomitant ACE inhibitor or ARB therapy: avoid combined use due to increased risk of renal dysfunction and hyperkalemia.
• Pregnancy: discontinue if pregnancy is confirmed, as safety data are limited.
• Hepatic impairment: use with caution in patients with moderate to severe liver disease.
• Store at ambient temperature: keep below 25°C in the original packaging, protect from moisture and direct sunlight.

Irbesartan can interact with several medicines, altering its efficacy or safety profile.

Major Interactions (Avoid)

• Concomitant use with ACE inhibitors or other ARBs: may cause additive renal impairment and hyperkalemia.
• Potassium‑sparing diuretics (e.g., spironolactone) or potassium supplements: increase risk of hyperkalemia.
• Strong CYP2C9 inhibitors (e.g., fluconazole): raise Irbesartan plasma concentrations.

Moderate Interactions (Monitor Closely)

• NSAIDs (e.g., ibuprofen): may reduce antihypertensive effect and affect renal function.
• Diuretics (e.g., thiazides): may enhance hypotensive response.
• Lithium: may increase lithium levels, requiring serum monitoring.