Diuretics DSA II Flashcards
osmotic agent pharmacy
given IV
- excreted in filtrate (30-60 mins)
- promotes water retention - proximal tubule and descending loop
- oppose ADH in collecting tubule
osmotic agent toxicity
extracellular volume expansion
-extracts water from cells prior to diuresis, leads to expansion of extracellular volume and hyponatremia
osmotic agent contraindication
renal disease, dehyration, pulmonary edema
osmotic agent clinical use
urinary excretion of toxic substance
- reduces intracranial and IOP
- use for prevention of ARF not reccommended
ADH agonists
increased water reabsorption
- vasopressin and desmopressin
- mediate vasoconstriction of vasc. smooth m and increase water permeability in collecting tubule
clinical use ADH agonists
diabetes insipidus, polyuria, polydipsia, hypernatremia, nocturnal uresis
ADH antagonists
SIADH, heart failure
-conivaptan and tolvaptan
demeclocycline
ADH antagonist
-not used - high renal failure incidence
tolvaptan
V2 receptor selectivity
conivaptan
antagonist at V1a and V2 receptors
toxicity of ADH antagonists
hypernatremia
nephrogenic diabetes insipidus
loop and thiazide combo
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
metolazone
thiazide diuretic
-often used in COMBO
combination use
not recommended for outpatient
-severe diuresis
K-sparing combo
with loop and thiazide agents
-to control hypokalemia
heart failure
edematous state - treated with diuretics
- decreased blood flow to kidney > salt and water retention
- pulmonary or interstitial edema can occur
Tx - diuretics decrease this
kidney disease
edematous state - treated with diuretics
- kidney diseases - result in Na and water retention
- severe loss of renal function - diuretic agents not worth much
early stage renal disease
hyperkalemia - loop and thiazide diuretics
hepatic cirrhosis
edema and ascites become severe due to liver diseas
aggressive use of diuretics - disaster in liver patient
HTN
non-edematous state- Tx diuretics
- thiazide - mild vasodilator
- loop - renal insufficiency or heart failure
nephrolithiasis
non-edematous state - Tx diuretics
- 2/3 stone calcium based
- thiazide increase Ca reabsorption and decreased urine Ca
hypercalcemia
non-edematous - Tx diuretics
-loop reduce Ca reabsorption and promote Ca diuresis
administer saline simultaneously
diabetes insipidus
non-edematous - Tx diuretics
-nephrogenic or neurogenic
- vasopressin/desmopressin - only central diabetes insipidus
- thiazide - reduce polyuria and polydipsia in both types
