Diuretics

Question 1

What are the classes of diuretics?

Answer 1

thiazides
loop
K sparing
CA inhibitors
Osmotics

Question 2

Osmotic diuretics increase urine flow with _____ salt excretion.

Answer 2

low

Question 3

Osmotic diuretics can cause an immediate inital ________ of the ECF.

Answer 3

expansion

Question 4

Mechanism of action for osmotic diuretics.

Answer 4

Osmotics distribute throughout the ECF and water moves out of the cells down the osmotic gradient. Expansion of ECF increases renal blood flow.

Question 5

Osmotic diuretics increases the excretion of which electrolytes?

Answer 5

All: Na, K, Ca, Mg, Cl, HCO3, PO4

Question 6

What are the osmotic diuretic agents?

Answer 6

Mannitol
Glycerin
Isosorbide

Question 7

Which osmotic diuretics are IV?

Answer 7

Mannitol

Question 8

Which osmotic diuretics are PO?

Answer 8

glycerine and isosorbide

Question 9

In what case would mannitol be contraindicated?

Answer 9

frank renal failure

pulmonary edema

Question 10

When is mannitol most commonly used?

Answer 10

shock
brain edema (trauma)
rhabdomyolysis

Question 11

When are glycerin and isosorbide commonly used?

Answer 11

before ophthalmic surgery

Question 12

What are the carbonic anhydrase inhibitor agents?

Answer 12

Acetazolamide (Diamox)
dichlorphenamide (Daranide)
methazolamide (Neptazane)

Question 13

What is the carbonic anhydrase inhibitor ending?

Answer 13

-amide

Question 14

What is one of the main limitations of carbonic anhydrase inhibitors?

Answer 14

excessive bicarbonate secretion and subsequent metabolic acidosis

Question 15

What are carbonic anhydrase inhibitors generally used for?

Answer 15

open-angle glaucoma
altitude sickness
alkalosis in CHF patients

Question 16

Mechanism of action of carbonic anhydrase inhibitors

Answer 16

reversible inhibition of carbonic anhydrase which prevents the formation of CO2 and the recovery of HCO3 from the tubule

Question 17

Carbonic anhydrase inhibitors are contraindicated in what groups?

Answer 17

pregnancy
hepatic cirrhosis
severe COPD

Question 18

What overdose situations would you use carbonic anhydrase inhibitors?

Answer 18

aspirin and barbituate

Question 19

What are the benzothiazide diuretic agents?

Answer 19

chlorothiazde
hydrochlorothiazide
hydroflumethiazide
methylchlothiazide
polythiazide
chlorthalidone
indapamide
metolazone

Question 20

What is the mechanism/site of action of benzothiazides?

Answer 20

Block the Na/Cl transporter in the early distal tubule

Question 21

What are the therapeutic uses of benzothiazides?

Answer 21

HTN
diabetes insipidus
kidney stones

Question 22

What is the first line diuretic (and antihypertensive)?

Answer 22

HCTZ

Question 23

Benzothiazides provide _____ diuresis.

Answer 23

mild/safe

Question 24

Benzothiazides lower BP by __-__ mm Hg

Answer 24

15-20

Question 25

How do benzothiazides improve diabetes insipidus?

Answer 25

In normo-natremic individuals, thiazides causes mild hyponatremia. This causes increased Na and water reabsorption in the proximal tubule meaning that less water reaches the distal tubule and thus urine output is decreased.

Question 26

How do benzothiazides treat kidney stones?

Answer 26

Thiazides decrease Ca exretion by unknown mechanism.

Question 27

What are the major adverse effects of benzothiazides?

Answer 27

hyPOkalemia hyPOmagnesia hyPERglycemia hyPERlipidemia

Question 28

Chlorthalidone is about ___x as potent as HCTZ and has about ___x the half life.

Answer 28

1.5x as potent | 18x longer half-life

Question 29

What are the loop diuretic agents?

Answer 29

furosemide (Lasix) bumetanide (Bumex) ethacrynic acid (Edecrin) torsemide (Demadex)

Question 30

For what conditions are loop diuretics commonly used?

Answer 30

edema hypercalcemia HTN unresponsive to thiazides renal failure

Question 31

Mechanism/site of action of loop diuretics

Answer 31

Blockade of the Na/K/2Cl uptake in the TALH

Question 32

Loop diuretics promote __ _______, potentially to a serious level.

Answer 32

K excretion

Question 33

Along with K, what other electrolytes do loop diuretics promote excretion?

Answer 33

Ca and Mg

Question 34

In the use of loop diuretics, renin secretion is/isn't suppressed.

Answer 34

Renin secretion is not suppressed

Question 35

In the use of loop diuretics, GFR is/is not reduced.

Answer 35

GFR is not reduced

Question 36

What are the adverse effects with loop diuretics?

Answer 36

``` electrolyte imbalances ototoxicity GI disturbances, bleeding, diarrhea pancreatitis lupus erythematosis ```

Question 37

Which loop diuretic agent is most common cause of ototoxicity?

Answer 37

ethacrynic acid

Question 38

What condition can be revealed by loop diuretics and thiazides?

Answer 38

gout

Question 39

Loop diuretics cause ____ diuresis.

Answer 39

high/potent

Question 40

Loop diuretics can interact with warfarin, causing _______ anticoagulation.

Answer 40

increased

Question 41

What are the K sparing diuretic agents?

Answer 41

Spironolactone Eplerenone Triamterene Amiloride

Question 42

In what conditions are K sparing diuretics used?

Answer 42

``` HTN CHF ascites (cirrhosis) primary and secondary aldosteronism hypokalemia ```

Question 43

How/where do the K sparing diuretics Triamterene and Amiloride work?

Answer 43

Triamterene and Amiloride block the Na channel in the late distal tubule and collecting duct.

Question 44

How/ where do the K sparing diuretics Spirololactone and Eplerenone work?

Answer 44

Spironolactone and Eplerenone are competitive antagonists of aldosterone at the mineralocorticoid receptor. They block the binding of aldosterone and thus decrease the synthesis and activity of the luminal Na channel.

Question 45

K sparing diuretics are _____ effective than ARBs in African Americans.

Answer 45

more

Question 46

Triamterene and Amiloride are/are not dependent on aldosterone levels.

Answer 46

are not

Question 47

Spironolactone and Eplerenone are/ are not dependent on aldosterone levels.

Answer 47

are

Question 48

K sparing diuretics are most effective when combined with _______ ________.

Answer 48

other diuretics

Question 49

Eplerenone has _______ specificity for MR than spironolactone.

Answer 49

greater

Question 50

What are the adverse effects of K sparing diuretics?

Answer 50

Hyperkalemia gynecomastia and impotence menstruel irregularities and hirsutism gastric bleeding

Question 51

Eplerenone is metabolized by _____ and shouldn't be used with inhibitors.

Answer 51

CYP3a4