(Furosemide, Ethacrynic acid, Bumetanide and Torsemide) DIURETICS: LOOP DIURETICS (Furosemide, Ethacrynic acid, Bumetanide and Torsemide) Loop diuretics selectively inhibit NaCl reabsorption in the ascending limb. Loop diuretics inhibit NKCC2, the luminal Na + /K + /2Cl − transporter in the ascending limb of Henle’s loop. Loop diuretics are the most efficacious diuretic agents currently available.

Furosemide increases renal blood flow….why? Both furosemide and ethacrynic acid have also been shown to reduce pulmonary oedema before a measurable increase in urinary output occurs. …… why? NSAIDs or probenecid, which compete for weak acid secretion in the proximal tubule.

Indications: Hypertension. Acute pulmonary edema and other edematous conditions. Acute hypercalcemia. Hyperkalemia. Acute renal failure.

Toxicity: Hypokalemic Metabolic Alkalosis Ototoxicity usually reversible. It enhanced if there is renal impairment or using other ototoxic drug like aminoglycoside antibiotics. Hyperuricemia Hypomagnesaemia Allergic and Other Reactions: All loop diuretics, with the exception of ethacrynic acid, are sulfonamides. interstitial nephritis may occur.

Thiazide diuretics Hydrochlorothiazide, Chlorthalidone, Chlorothiazide …etc. They increase sodium and water Potassium-sparing diuretics are often used in combination with thiazides to reduce the amount of potassium loss induced by the thiazide diuretics. Their action is take place predominantly in the DCT by blocking the Na+ /Cl− transporter (NCC). They may compete with uric acid for elimination. thiazides actually enhance Ca2+ reabsorption.

Indications: Useful in the treatment of black and elderly patients They are not effective in patients with inadequate kidney function (creatinine clearance, less than 50 mL/min) Hypertension Heart failure Nephrolithiasis due to idiopathic hypercalciuria. Nephrogenic diabetes insipidus.

Side effects: Hyponatremia Hypokalemia Hyperuricemia Hyperglycemia Hypomagnesemia Acute gouty attack.