Loop diuretics

Question 1

Osmotic diuretic

Answer 1

Mannitol

Question 2

Clinical use of mannitol

Answer 2

Drug overdose, elevated intracranial/intraocular pressure

Question 3

Toxicity of mannitol

Answer 3

Pulmonary edema, dehydration

Question 4

Contraindications of mannitol

Answer 4

Anuria, HF

Question 5

CA inhibitor in proximal tubule

Answer 5

Acetazolamide

Question 6

Effect of acetazolamide on HCO3- stores

Answer 6

Self-limited HCO3- diuresis, decrease in total body stores. Is unable to leave tubule (can’t be converted)

Question 7

Use for acetazolamide

Answer 7

Glaucoma, urinary alkalinization, metabolic alkalosis, altitude sickness, pseudotumor cerebri

Question 8

Acetazolamide toxicity

Answer 8

Hyperchloremic metabolic acidosis, paresthesias, NH3 toxicity, sulfa allergy

Question 9

Loop diuretics

Answer 9

Furosemide, bumetanide, torsemide, ethacrynic acid

Question 10

Sulfa loop diuretics

Answer 10

Furosemide, bumetanide, torsemide

Question 11

Loop diuretic, NOT a sulfa

Answer 11

Ethacrynic acid

Question 12

MOA of loop diuretics

Answer 12

Inhibition of NKCC transport system (thick ascending loop of Henle). Prevents concentration of urine

Question 13

Effect of loop diuretics on Ca2+ conc.

Answer 13

Increases calcium excretion.

Loops LOSE Ca2+.

Question 14

Inhibitor of loop diuretics

Answer 14

NSAIDs

Question 15

Clinical use of loop diuretics

Answer 15

Edematous states (HF, cirrhosis, nephrotic syndrome, pulm edema), HTN, hypercalcemia

Question 16

Clinical use of ethacrynic acid

Answer 16

Diuresis in pts with sulfa allergies

Question 17

Toxicity of loop diuretics

Answer 17

OH DANG

Ototoxicity, hypokalemia, dehydration, allergy, nephritis, gout

Question 18

Thiazide diuretics (examples)

Answer 18

Chlorthalidone, HCTZ

Question 19

MOA of thiazide diuretics

Answer 19

Inhibit NaCl reabsorption in early DCT, decreasing diluting capacity of nephron. Decreases Ca2+ excretion.

Question 20

Site of thiazide action

Answer 20

Distal tubule

Question 21

Clinical use of thaizides

Answer 21

HTN, HF, idiopathic hypercalciuria, nephrogenic diabetes insipidus, osteoporosis

Don’t use with renal insufficiency

Question 22

Toxicity of thiazides

Answer 22

sulfa allergy; HyperGLUC
hyponatremia, hyperGlycemis
hyperLipidemia
hyperUricemia
hyperCalcemia

Question 23

K+ sparing diuretics (examples)

Answer 23

Spironolactone/eplerenone
Triamterene
Amiloride
K+ STAys

Question 24

K+ sparing MOA

Answer 24

-one blocks aldosterone binding
Spironolactone/eplerenone thus increase Na+ and H2O excretion

Triamterene and amiloride act in corticol collecting tubule by blocking Na+ channels in cortical collecting tubule

Question 25

Use of K+ sparing agents

Answer 25

Hyperaldosteronism, K+ depletion, HF

Question 26

Toxicity of K+ sparing agents

Answer 26

Hyperkalemia (arrhythmias)

spironolactone causing endocrine effects

Question 27

Main overarching fxn of diuretics

Answer 27

Reduce volume by increasing Na+ and Cl- excretion

Question 28

Water permeable limb of the Loop of Henle

Answer 28

Thin descending limb

Question 29

ADH antagonists (name)

Answer 29

Demeclocycline, lithium, tolvaptan, conivaptan, mozavaptan

Question 30

Proximal tubule CA inhibitors

Answer 30

Acetazolamide, dichlorphenamide, methazolamide,

dorzolamid

Question 31

Use of metolazone

Answer 31

Strongest inhibitor of Na+ and water reabsorption within thiazide class. May be used in renal insufficiency. Can also be used in combination with a loop diuretic.