Irbesartan + Hidroclorotiazida Generis (Hydrochlorothiazide, Irbesartan)

Irbesartan/Hydrochlorothiazide is indicated for the management of elevated blood pressure within the antihypertensive drug class.

• Hypertension: reduces systolic and diastolic blood pressure, helping to prevent cardiovascular complications.
• Essential hypertension: improves blood pressure control when monotherapy is insufficient.
• High blood pressure in adults: provides combined vasodilation and diuretic effects for better therapeutic outcomes.

• Irbesartan selectively blocks AT1 receptors, preventing angiotensin II from causing vasoconstriction and aldosterone release, which leads to vasodilation and reduced blood volume. Hydrochlorothiazide inhibits sodium‑chloride reabsorption in the distal convoluted tubule, increasing urinary excretion of water and electrolytes, thereby decreasing plasma volume and further lowering blood pressure.

Common Side Effects

• Dizziness or light‑headedness
• Headache
• Fatigue or weakness
• Increased urination
• Electrolyte disturbances (e.g., low potassium)
• Mild gastrointestinal discomfort

Serious or Rare Side Effects

• Severe dehydration or electrolyte imbalance
• Acute kidney injury or worsening renal function
• Hyperkalemia or severe low potassium
• Angioedema or swelling of face, lips, tongue
• Significant hypotension leading to fainting
• Allergic reactions such as rash or hives

Patients should be monitored regularly for blood pressure, renal function, and electrolyte levels.

• Monitor blood pressure: ensure therapeutic targets are reached without excessive lowering.
• Assess renal function: check creatinine and eGFR before and during therapy.
• Check electrolytes: especially potassium and sodium levels.
• Avoid use in pregnancy: drug is classified as Category D and may harm the fetus.
• Use caution in elderly: increased sensitivity to blood pressure changes.
• Store at room temperature: keep in the original container, protect from moisture and direct sunlight.

Irbesartan/Hydrochlorothiazide may interact with several medications.

Major Interactions (Avoid)

• Aliskiren: combined use can increase risk of renal impairment and hyperkalemia.
• Potassium‑sparing diuretics or supplements: may cause dangerous hyperkalemia.
• Lithium: increased lithium levels leading to toxicity.
• ACE inhibitors or other ARBs: additive effect on potassium and renal function.
• NSAIDs (high dose): can reduce antihypertensive efficacy and impair renal function.

Moderate Interactions (Monitor Closely)

• CYP2C9 inhibitors (e.g., fluconazole): may increase irbesartan plasma concentrations.
• Other antihypertensives: may cause additive blood pressure lowering.
• Antidiabetic drugs: diuretic effect may affect glucose control.
• Anticoagulants: diuretic‑induced volume changes may alter drug levels.
• Thiazide‑sensitive drugs (e.g., digoxin): monitor for toxicity due to electrolyte shifts.