DIURETICS
Introduction:
Diuretics are drugs that increase urine output by acting on the kidneys. They promote the excretion of water and electrolytes such as sodium, chloride, and bicarbonate by reducing tubular reabsorption.
Classification of Diuretics:
- Carbonic anhydrase inhibitors: Acetazolamide
- Thiazide diuretics: Hydrochlorothiazide, Benzthiazide
- Loop diuretics: Furosemide, Bumetanide
- Potassium-sparing diuretics: Spironolactone
- Osmotic diuretics: Mannitol
- Miscellaneous: Metolazone, Xipamide
Important Drugs:
Acetazolamide:
Carbonic anhydrase inhibitor that increases excretion of sodium, potassium, and bicarbonate, producing alkaline urine.
- Glaucoma
- Epilepsy
- Mountain sickness
Furosemide:
Loop diuretic that inhibits Na⁺–K⁺–2Cl⁻ transporter in the loop of Henle, producing strong diuresis.
- Edema
- Hypertension
Bumetanide:
Potent loop diuretic used when response to furosemide is inadequate.
- Severe edema
Chlorthalidone:
Thiazide-like diuretic used for long-term control of hypertension.
- Hypertension
- Edema
Benzthiazide:
Thiazide diuretic that increases excretion of sodium and water.
- Hypertension
- Fluid retention
Metolazone:
Thiazide-like diuretic effective in resistant edema and hypertension.
- Heart failure edema
- Hypertension
Xipamide:
Promotes excretion of sodium and potassium while reducing calcium loss.
- Hypertension
- Edema
Spironolactone:
Potassium-sparing diuretic that blocks aldosterone receptors and prevents potassium loss.
- Edema
- Hypokalaemia
- Hypertension
