Diuretics

Question 1

Diuretic

• Osmotic: Amount filtered exceeds tubular transport–> some left in urine–> draws water into urine
• Treat oliguric renal failure, cerebral edema, acute glaucoma
• Don’t use if there is intracranial bleeding

Answer 1

Mannitol

Question 2

Diuretic

• Carbonic anhydrase inhibitor–> increased loss of bicarb–> increase urine pH–> acidified blood–> CO2 diffuses across membrane–> water follows into urine
• Weak diuretic effect
• May cause hypokalemia, basic urine, blood acidosis
• Treat metabolic alkalosis, glaucoma

Answer 2

Acetazolamide

Question 3

Loop diuretic–> inhibit NaCl reabsorption in thick ascending limb of loop of Henle

• Most effective diuretic, most commonly used
• May cause hypokalemia, and increase urinary calcium loss
• Treat exercise induced pulmonary hemorrhage, oligouric renal failure, and urinary blockage

Answer 3

Furosamide

Question 4

Thiazide diuretic

• Acts in distal tubule
• Blocks NaCl pump–> more NaCl in lumen–> water follows
• Increases in Ca reabsorption = need to get Na into cell from tissue using Na/Ca pump–> Ca pumped into blood vessel to get Na from lumen into cell–> replace with Ca from lumen
  
  • Treat Ca containing uroliths, udder edema, nephrogenic diabetes incipiduds
• Cause loss of K+

Answer 4

Chlorothiazide

Question 5

Diuretic

• Competitive aldosterone antagonist –> decreases Na-K exchange–> more Na in urine, less K in urine
• K+ sparing
• Delayed onset of action and prolonged effect
• Only a mild diuretic on it’s own, but will stop loss of K from other diuretics

Answer 5

Spironolactone

Question 6

Diuretic

• Principal cell Direct Na+ Channel blocker
• K+ sparing
• Immediate effect
• Mild diuretic alone, but stops K loss from other diuretics

Answer 6

Amiloride

Question 7

Diuretic
-Aquaretic–> blocks Antidiuretic hormone receptor–> no aquaporins inserted in collecting duct cells’ membranes–> water can’t flow back into tissues

Answer 7

Demecycline