Irbesartan + Hidroclorotiazida Alter (Hydrochlorothiazide, Irbesartan)

Irbesartan/Hydrochlorothiazide is used in the management of hypertension, acting on the renin‑angiotensin‑aldosterone system and fluid balance.

• Primary hypertension: reduces systolic and diastolic blood pressure in patients with essential hypertension.
• Hypertension with fluid retention: improves blood pressure control by adding diuretic effect.
• Resistant hypertension: provides additional lowering when monotherapy is insufficient.

• Irbesartan selectively blocks AT1 receptors, preventing angiotensin II‑mediated vasoconstriction and aldosterone release. Hydrochlorothiazide inhibits sodium‑chloride reabsorption in the distal convoluted tubule, promoting diuresis and decreasing plasma volume. The combined actions lower peripheral resistance and cardiac preload, resulting in sustained blood pressure reduction.

Common Side Effects

• Dizziness or light‑headedness.
• Headache.
• Increased urination or mild electrolyte changes.
• Fatigue or mild gastrointestinal discomfort.

Serious or Rare Side Effects

• Severe dehydration or electrolyte imbalance (e.g., hyponatremia, hypokalemia).
• Acute kidney injury or worsening renal function.
• Hyperkalemia, especially when combined with potassium‑sparing agents.
• Angioedema or severe allergic reactions.
• Blood dyscrasias such as agranulocytosis.

Before initiating therapy, consider the following precautions:

• Renal function monitoring: assess serum creatinine and eGFR regularly.
• Electrolyte balance: check potassium and sodium levels, especially in patients on other diuretics.
• Caution in elderly: start at lower doses to reduce risk of hypotension.
• Avoid in severe hepatic impairment: drug metabolism may be altered.
• Do not combine with potassium‑sparing diuretics or supplements without supervision.
• Store at ambient temperature: keep in original container, protect from moisture and direct sunlight.

Irbesartan/Hydrochlorothiazide may interact with several medicines.

Major Interactions (Avoid)

• Aliskiren in diabetic patients: increased risk of renal impairment.
• Lithium: may raise lithium levels, leading to toxicity.
• NSAIDs: can blunt antihypertensive effect and affect renal function.
• Potassium supplements or ACE inhibitors: risk of hyperkalemia.

Moderate Interactions (Monitor Closely)

• Other diuretics (non‑potassium‑sparing): monitor electrolytes and volume status.
• CYP3A4 inhibitors (e.g., ketoconazole): may increase irbesartan concentrations.
• CYP3A4 inducers (e.g., rifampin): may reduce irbesartan effectiveness.