Diuretics

Question 1

list the loop diuretics

Answer 1

1. furosemide
2. bum|eta|nide
3. ethacrynic acid

Question 2

duration of onset and lasting

Answer 2

quick onset
short lasting

Question 3

MOA of loop diuretics

Answer 3

inhibit Na+/ K+/ 2 Cl- transporter
= osmotic diuresis
= cannot accumulate K+ in the cell
= no lumen-positive electrical potential
= Mg2+ and Ca2+ not reabsorbed
= excretion of Mg2+ and Ca2+
= H2O follows
= diuretic

increase renal prostaglandin synthesis

Question 4

when are loop diuretics used

Answer 4

ACUTE ANYTHING
1. oedema (acute pulmonary oedema)
2. acute K+ (hyperkalemia)
3. acute renal failure
4. acute anion overdose

Question 5

contraindications of loop diuretics

Answer 5

do NOT give when…
- hypertension

DDI with
- aminoglycosides = ototoxicity
- NSAIDs = reduce PG synthesis (intefere with loop diuretics which induce PG synthesis)

Question 6

ADRs of loop diuretics

Answer 6

1. low K+ (hypokalemia)
   increase Na+ reabsorption
   = increase H+ release
   = increase pH
   = metabolic alkalosis
2. hyperuricemia
   too much uric acid absorbed back with H20
3. hypomagnesia
   Mg2+ excreted
   (but hypocalcemia unlikely, as Ca2+ absorbed in DCT again)

Question 7

what are the thiazides

Answer 7

IHC (inter healthcare camp) –> think ‘TRIazides’

1. inda|pa|mide
2. hydro|chloro|thiazide
3. chlor|tha|lidone

Question 8

where do thiazides work + MOA

Answer 8

DCT

1. inhibits NaCl co transpoter
   = more Na+ in urine at DCT
   = H2O follow
   = diuretic effect
2. enhance Ca2+ reabsorption in DCT
3. induce renal PG synthesis

Question 9

when are thiazides given

Answer 9

1. hypertension
2. CHF

Question 10

contraindications of thiazides

Answer 10

hyperuricemia

Question 11

ADRs of thiazides

Answer 11

hypokalemic metabolic alkalosis

body tries to reabsorb water but HCO3- is absorbed too
= metabolic alkalosis

Question 12

similarities between loop diuretics and thiazides

Answer 12

1. induce renal PG synthesis
2. ADR: hypokalemic metabolic alkalosis

Question 13

what is the alternative name for K+ sparing diuretics

Answer 13

aldosterone antagonists
ADH antagonists

Question 14

what are the K+ sparing diuretic drugs

Answer 14

STAE

spiro|no|lactone
tri|am|terene
ami|loride
eplere|none

Question 15

MOA of K+ sparing diuretic drugs

Answer 15

K+ sparing diuretic drugs
(aka. aldosterone antagonist)

SE:
block aldosterone receptor
= downregulate Na+ channel
= decrease Na+ reabsorption
= decrease K+ secretion (K+ sparing diuretic drugs)

TA:
block Na+ channel
= decrease K+ secretion

Question 16

when are K+ sparing diuretics used

Answer 16

1. hepatic cirrhosis
2. hyperaldosteronism

Question 17

STAE individual notices

Answer 17

S: slow onset
T: hepatic metabolism, short half life = more frequent doses required
A: longer half life, excreted ynchanced in the urine
E: potential kidney stones, NO gynecomastia

Question 18

ADRs of K+ sparing diuretics

Answer 18

decrease K+ secretion
= hyperkalemia

metabolic ACIDOSIS