Exam 1; Diuretics Flashcards Preview

AU14 Pharmacology > Exam 1; Diuretics > Flashcards

Flashcards in Exam 1; Diuretics Deck (37):
1

What is the definition of a diuretic

any agent that causes a net excretion of water and Na+

2

What two main things are diuretics used for clinically

hypertension; decreasing blood volume and some cause vasodilation
to reduce edema; in heart failure; kidney retains H2O and Na, water accumulates in the interstitial space

3

This is designed to eliminate unwanted molecules (Na & H2O) and to conserve essential ions and molecules

normal kidney function

4

What is the flow of molecules in the proximal convoluted tubule

removal of Ca++, Na+, HCO3-
exchange of organic molecules

5

What is the flow of water through the renal tubule

water can freely pass through the tubule; following the osmotic gradient

6

What is the flow of molecules in the loop of Henle

removal of K+, Cl-, and large amounts of Na

7

What is the flow of molecules in the distal convoluted tubule

removal of Na+, Cl-, Ca++

8

What is the flow of ions in the collecting duct

Na+/K+ exchanger (Na out, K in)
removal of H2O

9

True or False
Thiazide diuretics have a low therapeutic index

False; they have a high index

10

What is the mechanism behind thiazide diuretics

they inhibit Na+ transport out of the DCT; water follows and they are excreted in the urine

11

What are two other affects of thiazide diuretics

they cause direct vasodilation (often drug of choice in treating hypertension)
they decrease the excretion of Ca++ (Ca++ retention)

12

What are five side effects of thiazide diuretics

hypokalemia (loss of Ka due to Na/K exchanger)
increase serum LDL and triglycerides
decrease uric acid secretion; gout
inhibit insulin secretion
contains sulfur ions; may cause allergic reaction

13

What are two examples of thiazide diuretics

chlorothiazide
hydrochlorothiazide

14

What are four examples of loop/high ceiling diuretics

furosemide
ethacryncic acid
bumetanide
torsemide

15

What is the mechanism of action of loop diuretics

given orally or parentally
inhibit Na/Cl resorption from the ascending limb of the loop of Henle

16

Which is more efficacious, thiazides or loop diuretics

loop

17

How much urine/day can a patient excrete while on loop diuretics

10L

18

When are loop diuretics given clinically

in patients that don't respond well to thiazides
patients with impaired renal function
patients with life threatening edema (pulmonary/cerebral)

19

What are 5 side effects of loop diuretics

dehydration
hypokalemia (more Na to exchanger)
hypocalcemia (increase Ca excretion)
decreased uric acid secretion
auditory nerve damage (especially if used with other ototoxic agents)

20

What are two examples of potassium-sparing diuretics; aldosterone antagonists

spironolactone
eplerenone

21

What is the mechanism behind potassium-sparing diuretics

blocking the aldesterone receptor; can prevent synthesis of Na/K+ exchanger

22

What are four side effects of potassium-sparing diuretics

takes a couple days to work
used with other diuretics to prevent K+ loss
used to treat excess aldesterone activity
can cause hyperkalemia

23

This potassium-sparing diuretic is a steroid, and can have anti-androgen effects (breast growth, etc.)

spironolactone

24

This potassium sparing diuretic has fewer interaction with other steroid receptors

eplerenone

25

These two potassium-sparing diuretics are inhibitors of what

triamterne
amiloride
Na+ transport in the distal tubule and collecting duct

26

Potassium-sparing diuretics which inhibit Na transport have what kind of mechanism

they prevent Na from getting into the exchanger by blocking Na channel

27

What is the effect/symptoms of potassium sparing diuretics which inhibit Na transport

the effect is more rapid and predictable than alderstone antagonists
hyperkalemia

28

What is the mechanism behind carbonic anhydrase (enzyme) inhibitors

inhibits HCO3- absorption in the PCT

29

What three things do carbonic anhydrase inhibitors (not primarily a diuretic) also treat

open angle glaucoma
mountain sickness (decrease CSF formation)
epilepsy (may be due to pH changes in the CNS)

30

This is an example of an osmotic diuretic

mannitol

31

What is the mechanism behind mannitol

non-metabolized sugar given as an IV and it remains in tubule and draws water into tubule and is secreted with the water

32

What is mannitol used to treat

used to maintain renal/urine flow after renal damage/trauma
also it lowers intracranial pressure

33

This diuretic increases globular filtration rate

methylxanthines (such as caffeine)

34

This diuretic releases ADH

ethanol

35

This triggers the synthesis of the Na/K exchanger

aldesterone

36

ADH (antidiuretic hormone) induces what

further reabsorption of H2O

37

This blocs the ADH receptor; in cases of excess ADH/retain too much water

conivaptin