Diuretics DSA II

Question 1

osmotic agent pharmacy

Answer 1

given IV

• excreted in filtrate (30-60 mins)
• promotes water retention - proximal tubule and descending loop
• oppose ADH in collecting tubule

Question 2

osmotic agent toxicity

Answer 2

extracellular volume expansion

-extracts water from cells prior to diuresis, leads to expansion of extracellular volume and hyponatremia

Question 3

osmotic agent contraindication

Answer 3

renal disease, dehyration, pulmonary edema

Question 4

osmotic agent clinical use

Answer 4

urinary excretion of toxic substance

• reduces intracranial and IOP
• use for prevention of ARF not reccommended

Question 5

ADH agonists

Answer 5

increased water reabsorption

• vasopressin and desmopressin
• mediate vasoconstriction of vasc. smooth m and increase water permeability in collecting tubule

Question 6

clinical use ADH agonists

Answer 6

diabetes insipidus, polyuria, polydipsia, hypernatremia, nocturnal uresis

Question 7

ADH antagonists

Answer 7

SIADH, heart failure

-conivaptan and tolvaptan

Question 8

demeclocycline

Answer 8

ADH antagonist

-not used - high renal failure incidence

Question 9

tolvaptan

Answer 9

V2 receptor selectivity

Question 10

conivaptan

Answer 10

antagonist at V1a and V2 receptors

Question 11

toxicity of ADH antagonists

Answer 11

hypernatremia

nephrogenic diabetes insipidus

Question 12

loop and thiazide combo

Answer 12

when acting alone doesn’t work
-more than an additive diuretic response
-thiazides mild natriuresis, blocked in increased thick ascending absorption - combo blocks Na reabsorption
>all three segments - PCT, ascending loop, DCT

Question 13

metolazone

Answer 13

thiazide diuretic

-often used in COMBO

Question 14

combination use

Answer 14

not recommended for outpatient

-severe diuresis

Question 15

K-sparing combo

Answer 15

with loop and thiazide agents

-to control hypokalemia

Question 16

heart failure

Answer 16

edematous state - treated with diuretics

• decreased blood flow to kidney > salt and water retention
• pulmonary or interstitial edema can occur

Tx - diuretics decrease this

Question 17

kidney disease

Answer 17

edematous state - treated with diuretics

• kidney diseases - result in Na and water retention
• severe loss of renal function - diuretic agents not worth much

Question 18

early stage renal disease

Answer 18

hyperkalemia - loop and thiazide diuretics

Question 19

hepatic cirrhosis

Answer 19

edema and ascites become severe due to liver diseas

aggressive use of diuretics - disaster in liver patient

Question 20

HTN

Answer 20

non-edematous state- Tx diuretics

• thiazide - mild vasodilator
• loop - renal insufficiency or heart failure

Question 21

nephrolithiasis

Answer 21

non-edematous state - Tx diuretics

• 2/3 stone calcium based
• thiazide increase Ca reabsorption and decreased urine Ca

Question 22

hypercalcemia

Answer 22

non-edematous - Tx diuretics
-loop reduce Ca reabsorption and promote Ca diuresis

administer saline simultaneously

Question 23

diabetes insipidus

Answer 23

non-edematous - Tx diuretics
-nephrogenic or neurogenic

• vasopressin/desmopressin - only central diabetes insipidus
• thiazide - reduce polyuria and polydipsia in both types