Natramid/Opumide (Indapamide Hemihydrate)

Indapamide is indicated for conditions where reduction of blood pressure or excess fluid is required.

• Hypertension: lowers systolic and diastolic blood pressure, helping to prevent cardiovascular complications.
• Edema associated with heart failure: promotes diuresis to decrease fluid overload and improve symptoms.
• Edema associated with renal disease: enhances urinary sodium and water excretion to reduce swelling.

• Indapamide acts on the distal convoluted tubule of the nephron by inhibiting the Na⁺/Cl⁻ cotransporter. This blockade reduces sodium and chloride reabsorption, leading to increased urinary excretion of water and electrolytes. The resulting plasma‑volume contraction lowers peripheral vascular resistance, contributing to its antihypertensive effect.

Indapamide may cause a range of adverse reactions, varying from mild to severe.

Common Side Effects

• Dizziness or light‑headedness
• Headache
• Nausea or abdominal discomfort
• Increased urinary frequency
• Electrolyte disturbances such as low potassium
• Photosensitivity or skin rash

Serious or Rare Side Effects

• Severe dehydration or electrolyte imbalance
• Acute gout attacks
• Pancreatitis
• Severe allergic reactions (e.g., Stevens‑Johnson syndrome)
• Blood dyscrasias such as agranulocytosis
• Hepatic dysfunction

When prescribing indapamide, clinicians should consider several safety measures.

• Monitor electrolytes: check serum potassium and sodium regularly.
• Assess renal function: evaluate creatinine clearance before initiation.
• Evaluate blood pressure: ensure adequate control and avoid excessive hypotension.
• Use caution in diabetes: diuretic may affect glucose control.
• Avoid in severe hepatic impairment: risk of accumulation.
• Store at room temperature: keep in the original container, protect from moisture.

Indapamide can interact with other medicines, altering its efficacy or safety.

Major Interactions (Avoid)

• Lithium: increased lithium levels may cause toxicity.
• Digoxin: enhanced digoxin concentrations can lead to arrhythmias.
• Cyclosporine: may raise cyclosporine levels and nephrotoxicity risk.

Moderate Interactions (Monitor Closely)

• Antidiabetic agents: diuretic‑induced hypokalemia can enhance insulin sensitivity, requiring dose adjustment.
• Other antihypertensives: additive blood‑pressure‑lowering effect may cause hypotension.
• Non‑steroidal anti‑inflammatory drugs (NSAIDs): may reduce diuretic efficacy and impair renal function.
• ACE inhibitors or ARBs: combined use can increase risk of renal impairment and hyperkalemia.