(3.1) Diuretics (Wolff)

Question 1

What are the (3) thaizide diuretics?

Answer 1

Hydrochlorothiazide

Metolazone

Chlorthalidone

Question 2

What are the (4) loop diuretics?

Answer 2

Furosemide

Torsemide

Bumetanide

Ethacrynic acid

Question 3

What are the K+ sparing diuretics (specifically the 2 Na+ channel blockers)?

Answer 3

Amiloride

Triamterene

Question 4

What are the K+ sparing diuretics (specifically the 2 aldosterone antagonists)?

Answer 4

Spironolactone

Eplerenone

Question 5

What is the carbonic anhydrase inhibitor?

Answer 5

Acetazolamide

Question 6

What is the osmotic diuretic?

Answer 6

Mannitol

Question 7

What are the (2) aquaretics?

Answer 7

”-vaptan”

Conivaptan

Tolvaptan

Question 8

Define:

Diuretic

Answer 8

Substance that promotes the excretion of urine

Question 9

Define:

Natriuetic

Answer 9

Substance that promotes the renal excretion of sodium

Question 10

Define:

Aquaretic

Answer 10

Substance that produces free water clearance

Question 11

What class of diuretics act at the proximal tubule?

Answer 11

Osmotic diuretics

Carbonic anhydrase inhibitors

Question 12

What class of diuretics act at the thick ascending limb of henle?

Answer 12

Loop diuretics

Question 13

What class of diuretics act at the distal convoluted tubule?

Answer 13

Thiazide

Question 14

What class of diuretics act at the cortical collecting duct?

Answer 14

Na+ channel blockers

(spironolactone)

Question 15

What class of diuretics act at the collecting duct?

Answer 15

-Vaptans

Question 16

What are the common clinical reasons for administering diuretics?

Answer 16

Essential hypertension

Edema (associated with liver/kidney/congestive heart failure)

Question 17

What’s a nice way to remember where the K+ losing vs K+ sparing diuretics act?

Answer 17

K+ losing act more proximal to the glomerulus

K+ sparing act more distal to the glomerulus

Question 18

Hyperkalemia causes _________ on EKGs

Answer 18

Hyperkalemia causes tall T waves on EKGs

Question 19

What is a paradoxical reaction of the heart to hyperkalemia?

Answer 19

BRADYCARDIA

Question 20

Hypokalemia causes _________ on EKGs

Answer 20

Hypokalemia causes flattened T waves and tall U waves on EKGs

Question 21

What is the mechanism of action of loop diuretics?

Answer 21

Block the Na+-K+-2Cl- cotransporter in the thick ascending limb

Question 22

Loop diuretics are efficacious even when ____ and ____ are low

Answer 22

Loop diuretics are efficacious even when RBF and GFR are low

Question 23

What are the adverse effects of loop diuretics?

Answer 23

Hypokalemia

Hypomagnesemia

Hypocalcemia

Ototoxicity

Question 24

What drug is among the few diruetics that can be used by people who are allergic to “sulfa drugs”?

Answer 24

Ethacrynic acid

Question 25

What is the mechanism of action of **thiazides?**

Answer 25

Block the **Na-Cl cotransporter** in the _distal convoluted tubule_

Question 26

Thiazides do NOT work well with _____ and/or \_\_\_\_\_\_

Answer 26

Thiazides do NOT work well with **low RBF** and/or **low GFR**

Question 27

Thizide diuretics are indicated for?

Answer 27

Primary hypertension Nephrogenic diabetes insipidus

Question 28

What are the **adverse effects** of **Thiazide** diuretics?

Answer 28

Hypovolemia K+ losing Hypochloremic metabolic alkalosis Hypomagnesemia

Question 29

What is the mechanism of action of **K+ sparing diuretics?**

Answer 29

Can be one of two mechanisms... 1) (Amiloride) Blocks the luminal **Na+** channels in the **collecting duct** 2) (Spironolactone) Blocks the **Aldosterone** receptor in the collecting duct

Question 30

Na+ channel blockers (amiloride and triamterene) exert their effects...

Answer 30

QUICKLY!!! Since the channel is blocked directly, effects are seen more rapidly than with **spironolactone**

Question 31

What is the mechanism of action of **spironolactone?**

Answer 31

Blocks the ability of **aldosterone** to bind to its receptor --\> leads to **increased Na+ excretion** and **decreased K+ excretion**

Question 32

What is notable about the pharmacokinetics of **spironolactone?**

Answer 32

Can take 48 hours to work!!! SO SLOW

Question 33

What are the adverse effects of **spironolactone?**

Answer 33

Hyperkalemia Endocrine effects (gynecomastia, impotence, menstrual irregularities, hirsutism and deepening voice)

Question 34

What is the mechanism of action of the **vaptans?**

Answer 34

Block the **antidiuretic hormone receptor** in the _collecting duct_

Question 35

What is the mechanism of action of **acetozolamide?**

Answer 35

Inhibits **carbonic anhydrase**

Question 36

What are the indications for **acetozolamide?**

Answer 36

Urinary alkalinization Glaucoma Acute **mountain sickness**

Question 37

What are the adverse effects of **acetazolamide?**

Answer 37

Hyperchloremic metabolic acidosis Renal stones Potassium wasting

Question 38

What is the mechanism of action of **mannitol?**

Answer 38

Mannitol is a non-metabolized sugar, freely filtered with **minimal reabsorption** The **inability to reabsorb** this solute keeps water in the proximal tubule lumen; this water is delivered to the distal portions of the nephron where much of it is **excreted**

Question 39

The net effect of administering mannitol is to...

Answer 39

Excrete **total body water** in excess of **plasma electrolytes**

Question 40

What is noteworthy about the pharmacokinetics of **mannitol?**

Answer 40

Given in GRAMS!!! A lot more than the other diuretics (eg 50-200grams)

Question 41

What are two examples of **alternative medicine** diuretics?

Answer 41

Herbal diuretics Licorice