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608 SeCTIOn III Renal ` RENAL—PhARmACoLogy Renal ` RENAL—PhARmACoLogy

Acetazolamide
mEChANism Carbonic anhydrase inhibitor. Causes self-
limited NaHCO diuresis and  total body
3
HCO stores. Alkalinizes urine.
−
3
CLiNiCAL UsE Glaucoma, metabolic alkalosis, altitude sickness,
idiopathic intracranial hypertension.

ADVERsE EFFECts Proximal renal tubular acidosis, paresthesias, “Acid”azolamide causes Acidosis.
NH toxicity, sulfa allergy, hypokalemia.
3
Promotes calcium phosphate stone formation
(insoluble at high pH).

Loop diuretics
Furosemide, bumetanide, torsemide
mEChANism Sulfonamide loop diuretics. Inhibit cotransport
−
system (Na /K /2Cl ) of thick ascending limb
+
+
of loop of Henle. Abolish hypertonicity of
medulla, preventing concentration of urine.
Associated with  PGE (vasodilatory effect on
afferent arteriole); inhibited by NSAIDs.  Ca
2+
excretion. Loops Lose Ca .
2+
CLiNiCAL UsE Edematous states (HF, cirrhosis, nephrotic
syndrome, pulmonary edema), hypertension,
hypercalcemia.
ADVERsE EFFECts Ototoxicity, Hypokalemia, Hypomagnesemia, OHH DAANG!
Dehydration, Allergy (sulfa), metabolic
Alkalosis, Nephritis (interstitial), Gout.
Ethacrynic acid

mEChANism Nonsulfonamide inhibitor of cotransport system
(Na /K /2Cl ) of thick ascending limb of loop
−
+
+
of Henle.
CLiNiCAL UsE Diuresis in patients allergic to sulfa drugs.
ADVERsE EFFECts Similar to furosemide, but more ototoxic. Loop earrings hurt your ears.

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