Irbesartan/Hydrochlorthiazid Stada (Hydrochlorothiazide, Irbesartan)

• Irbesartan/Hydrochlorothiazide is used to manage high blood pressure and related cardiovascular conditions.
• Essential hypertension: lowers systolic and diastolic blood pressure to reduce cardiovascular risk.
• Secondary hypertension: helps control blood pressure when it results from another underlying disorder.
• Hypertension with fluid retention: combines vasodilation and diuresis to reduce excess fluid and pressure.

• Irbesartan selectively blocks angiotensin II type 1 (AT1) receptors, preventing vasoconstriction and aldosterone release, while hydrochlorothiazide inhibits the Na+/Cl‑ symporter in the distal convoluted tubule, promoting sodium and water excretion. The combined actions decrease peripheral vascular resistance and plasma volume, leading to a sustained reduction in arterial blood pressure.

Common Side Effects

• Dizziness or light‑headedness, especially after the first doses.
• Headache or mild fatigue.
• Increased urinary frequency due to the diuretic component.
• Electrolyte changes such as low potassium or sodium.
• Mild gastrointestinal discomfort.

Serious or Rare Side Effects

• Severe dehydration or electrolyte imbalance requiring medical attention.
• Acute kidney injury or worsening renal function.
• Hyperkalemia, particularly when combined with potassium‑sparing agents.
• Anaphylactic or severe allergic reactions.
• Blood dyscrasias such as agranulocytosis or thrombocytopenia.

Before initiating therapy, consider the following precautions:

• Renal function: assess baseline kidney function and monitor periodically.
• Electrolytes: check serum potassium and sodium levels, especially in patients on other diuretics.
• Pregnancy: avoid use unless clearly needed, as safety data are limited.
• Concomitant drugs: review for potential interactions that may affect blood pressure or electrolytes.
• Elderly patients: start at lower doses and monitor for orthostatic hypotension.

Store at ambient temperature below 25°C: keep in the original container, protect from moisture and direct sunlight.

Irbesartan/Hydrochlorothiazide may interact with several medicines.

Major Interactions (Avoid)

• Potassium‑sparing diuretics or supplements: risk of hyperkalemia.
• Lithium: increased lithium levels and toxicity.
• ACE inhibitors or other ARBs: additive effects on blood pressure and renal function.
• NSAIDs: may reduce antihypertensive efficacy and impair renal function.

Moderate Interactions (Monitor Closely)

• Other antihypertensives: may cause excessive hypotension.
• Antidiabetic agents: diuretic may affect glucose control.
• CYP2C9 inhibitors (e.g., amiodarone): may increase irbesartan plasma levels.