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including furosemide, bumetanide, and torsemide, reversibly inhibit the sodium-potassium-two chloride cotransporter at the luminal thick ascending limb of the loop of Henle, therefore inhibiting the reabsorption of sodium, potassium, and chloride ions. Loop diuretics produce relatively more urine formation and less loss of sodium and potassium than thiazides. Thiazide diuretics inhibit sodium and chloride reabsorption via the inhibition of sodium-chloride cotransporter in the distal tubule. This cotransporter is insensitive to loop diuretics. Spironolactone is a powerful potassium-sparing diuretic that inhibits the binding of aldosterone to mineralocorticoid receptors in many tissues, including epithelial cells of the distal convoluted tubule and collecting duct. This will increase sodium and water loss and spare potassium. Other potassium-sparing diuretics such as amiloride and triamterene act by inhibiting the sodium-hydrogen exchanger and indirectly decreasing potassium loss. They are relatively weak diuretics, which are often used in combination with thiazides and loop diuretics to increase sodium excretion without a major potassium loss.

Diuretics induce a loss of electrolytes and fluid, thereby stimulating several compensatory hemostatic mechanisms such as the RAS, which result in increased renal sodium retention by all nephron segments, a phenomenon known as diuretic resistance. If dietary salt intake is sufficiently high, a daily net negative sodium balance may not be achieved even with several daily doses of loop diuretics. Hence, salt intake must be restricted in patients with hypertension and heart failure to obtain a negative sodium balance.

The major side effect of loop and thiazide diuretics is the deficiency of the main electrolytes, particularly sodium and potassium. Hypokalemia may increase the risk of arrhythmia and cardiac arrest. Mild hypokalemia caused by these diuretics may result in leg cramps, polyuria, and muscle weakness. Most diuretics also decrease urate excretion and increase blood uric acid, causing gout in predisposed patients. Serum cholesterol levels may increase after diuretic therapy, and high doses of diuretics can impair glucose tolerance and precipitate diabetes mellitus, probably through an increase in insulin resistance.63

Diabetes 2

Diabetes 2

Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...

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