What are the classes of diuretics and their representative agents?

From the Guidelines

Diuretics are classified into several major categories, including loop diuretics, thiazide and thiazide-like diuretics, and potassium-sparing diuretics, with representative agents such as furosemide, hydrochlorothiazide, and spironolactone, respectively. The classes of diuretics and their mechanisms of action are as follows:

• Loop diuretics, which include bumetanide, furosemide, and torsemide, inhibit reabsorption of sodium or chloride at the loop of Henle 1.
• Thiazide and thiazide-like diuretics, such as chlorthalidone or hydrochlorothiazide, act in the distal convoluting tubule 1.
• Potassium-sparing diuretics, including spironolactone, act in the collecting duct 1. These diuretics are used to treat various conditions, including heart failure, hypertension, and fluid retention, with the goal of eliminating clinical evidence of fluid retention while maintaining euvolemia 1. The choice of diuretic depends on the clinical situation, with consideration of electrolyte balance and potential side effects, and should be used in combination with other guideline-directed medical therapy for heart failure that reduces hospitalizations and prolongs survival 1. In patients with refractory edema, metolazone or chlorothiazide may be added to loop diuretics, and in patients with hyponatremia, vasopressin antagonists may be helpful in the acute management of volume overload 1.

From the FDA Drug Label

Diuretics such as chlorthalidone are indicated in the management of hypertension either as the sole therapeutic agent or to enhance the effect of other antihypertensive drugs in the more severe forms of hypertension. Torsemide is a diuretic of the pyridine-sulfonylurea class.

The classes of diuretics and their representative agents are:

• Thiazide diuretics: hydrochlorothiazide
• Pyridine-sulfonylurea diuretics: torsemide
• Thiazide-like diuretics: chlorthalidone 2, 3, 4

From the Research

Classes of Diuretics

The classes of diuretics include:

• Thiazides and thiazide-like agents, which inhibit sodium reabsorption in the early distal convoluted tubule 5
• Loop diuretics, such as furosemide, which block chloride and sodium reabsorption by inhibition of the Na/K/2Cl cotransport system in the thick ascending limb of the loop of Henle 5, 6, 7
• Potassium-sparing (retaining) diuretics, including:
  • Aldosterone receptor blockers (such as spironolactone and eplerenone) 5, 8
  • Epithelial sodium channel blockers (such as amiloride and triamterene) 5, 7, 8

Representative Agents

Some representative agents of these classes include:

• Thiazides: hydrochlorothiazide, chlorthalidone, indapamide 5, 6, 7, 8
• Loop diuretics: furosemide, torasemide 5, 6, 7, 9
• Potassium-sparing diuretics: spironolactone, eplerenone, amiloride, triamterene 5, 7, 8