Diuretics

Question 1

Carbonic anhydrase inhibitor:

Answer 1

Acetazolamide

Question 2

Carbonic anhydrase inhibitor effects (4):

Answer 2

• Weak diuretic
• Na+ excretion (5% filtered load Na+, H2O)
• HCO3- excretion –> metabolic acidosis
• K+ excretion

Question 3

Carbonic anhydrase inhibitor therapeutic uses (3):

Answer 3

• Decrease intraocular pressure (OA glaucoma)
• Urinary alkalization
• Mountain sickness prophylaxis

Question 4

Carbonic anhydrase inhibitor adverse effects (4):

Answer 4

• Metabolic acidosis
• Hypokalemia
• Drowsiness
• Hypersensitivity (sulfonamides)

Question 5

Thiazide MOA:

Answer 5

Inhibition of luminal Na+, Cl- cotransport

- Binds to Cl- binding site

Question 6

Thiazide site of action:

Answer 6

Distal tubule

Question 7

Thiazide effects on urine composition (4):

Answer 7

• Na+ and H2O excretion (10% filtered load - modest)
• K+, Cl-, HCO3- excretion
• Decreased Ca2+ excretion
• Decreased uric acid excretion

Question 8

Thiazide therapeutic uses (5):

Answer 8

• HTN (main use)
• CHF, other edema states
• Hypercalciuric renal stones
• Nephrogenic DI
• Nephrotic syndrome (with spironolactone)

Question 9

Only thiazide-related drugs effect at lower GFR rates (2):

Answer 9

• Metolazone

- Inadapamide

Question 10

Thiazide ADRs (7):

Answer 10

• Hypokalemia (digitalis interaction)
• Hypovolemia (rare)
• Hyperglycemia (diabetics)
• Hyperuricemia (gout pts)
• Hypercalcemia
• Hypersensitivity (sulfonamide)
• Hyperlipidemia

Question 11

Loop diuretic that is NOT a sulfonamide:

Answer 11

Ethacrynic acid

Question 12

Loop diuretics MOA:

Answer 12

Inhibit Na+, K+, 2Cl- cotransport (at Cl- binding site)

Question 13

Loop diuretics site of action:

Answer 13

Ascending limb of loop of Henle

Question 14

Loop diuretic effects (4):

Answer 14

• Na+ and H20 excretion (25%)
• K+, Cl- excretion
• Ca2+ excretion
• +/- HCO3- excretion (higher doses)

Question 15

Loop diuretic therapeutic uses (4):

Answer 15

• Acute pulmonary edema (IV use)
• Edema (CHF, renal, hepatic)
• HTN (low GFR)
• Hypercalcemia

Question 16

Loop diuretic ADRs (7):

Answer 16

• Hypovolemia
• Hypokalemia
• Ototoxicity (hearing loss, additive)
• Hyperuricemia
• Hyperglycemia
• Hypersensitivity (Sulfa - not EA)
• Hyperlipidemia

Question 17

Potassium-sparing diuretics (4):

Answer 17

• Triamterene
• Amiloride
• Spionolactone
• Eplerenone

Question 18

Aldosterone receptor antagonists (2):

Answer 18

• Spironolactone

- Eplerenone

Question 19

Aldosterone receptor antagonist MOA:

Answer 19

Competitive antagonist at renal aldosterone receptors

- Decreased Na+/K+ exchange in distal tubule and collecting duct

Question 20

Aldosterone receptor antagonist effect on urine composition (2):

Answer 20

• Increased Na+, Cl-, H2O excretion (2-3%)

- Decreased K+, H+

Question 21

Spironolactone therapeutic uses (4):

Answer 21

• Primary hyperaldosteronism
• Prevent hypokalemia with K+ depleting diuretics
• Edema from hepatic cirrhosis and nephrotic syndrome (DoC)
• CHF

Question 22

Eplerenone therapeutic uses (2):

Answer 22

• HTN

- CHF post-MI

Question 23

Aldosterone receptor antagonist ADRs (2):

Answer 23

• Hyperkalemia

- Altered hormonal activity

Question 24

Sodium channel blockers (2):

Answer 24

• Triamterene

- Amiloride

Question 25

Sodium channel blockers MOA:

Answer 25

Decrease Na+/K+ exchange in distal tubule and collecting duct

Question 26

Sodium channel blocker effects (2):

Answer 26

- Decreased K+, H+ secretion | - Increased Na+, Cl-, H2O excretion (2-3%)

Question 27

Sodium channel blocker therapeutic uses (2):

Answer 27

- Secondary hyperaldosteronism | - Prevent hyokalemia of K+ depleting diuretics

Question 28

Osmotic diuretic effects (3):

Answer 28

- Increased urinary flow - Slight Na+ excretion - Decreased urine osmolarity

Question 29

Osmotic diuretic therapeutic uses (4):

Answer 29

- Maintain urine flow - Acute renal failure - Reduce intracranial pressure - Glaucoma (decreases intraocular pressure)