Diuretics

Question 1

Mechanism of action of Actetazolamide, Methazolamide and Dichlorphenamide?

Answer 1

Inhibit carbonicanhydrase in PT, preventing HCO3/Na reabsorption

Question 2

Side effects of the carbonic anhydrase inhibitors?

Answer 2

Hypokalemia; metabolic acidosis; hepatic encephalopathy

Question 3

According to lecture carbonic anhydrase inhibitors are relatively obsolete for use in diuresis; what other conditions can these drugs be used for?

Answer 3

Decreasing intraocular pressure/volume; Acute mountain sickness

Question 4

List the three example carbonic anhydrase inhibitors:

Answer 4

acetazolamide, methazolamide and dichlorphenamide (-zolamide or -amide)

Question 5

What are the uses of osmotic diuretics such as mannitol?

Answer 5

Increase drug excretion; minimize kidney damage in shock; Decrease CNS pressure

Question 6

What are some side effects of osmotic diuretics such as mannitol? What pathological condition mimics the action of an osmotic diuretic?

Answer 6

Increased systemic osmotic pressure; pulmonary edema. Also H2O is excreted in greater proportion vs. Na. Glucose can act in similar method in poorly controlled DM

Question 7

FuroSEMIDE, TorSEMIDE and Bumetanide are examples of what class of diuretic? What is their mechanism of action?

Answer 7

Loop Diuretics; Inhibits Na/K/2Cl in the talH; Also effects Ca/Mg reabsorption

Question 8

What is another loop diuretic that can be used in patients who are allergic to furosemide, torsemide and bumetanide?

Answer 8

Ethacrynic acid

Question 9

What are some common side effects of the loop diuretics?

Answer 9

HypERuricemia; hyponatremia; hypokalemia; hypocalcemia; Low Mg; ototoxicity; DM unmasking; Erectile dysfunction

Question 10

Chlorothiazide and hydrochlorothiazide are the thiazide diuretics; what were the four thiazide-like diuretics in the lecture notes? Where is their site of action in the nephron?

Answer 10

Chlorthalidone MetolAZONE QuinethAZONE. Indapamide. Thiazide and thiazide-like diuretics all act in the early distal tubule

Question 11

What are the three potassium sparing diuretics? Which one is aldosterone dependent?

Answer 11

Spironolactone, triamterene and amiloride. Spironolactone is aldosterone dependent

Question 12

Where does aminophylline act in the nephron?

Answer 12

The proximal tubule