Diuretics Flashcards
mannitol
osmotic
Acetazolamide
Carbonic Anhydrase Inhibitor
furosemide
loop diuretic, renal elimination, 1.5 hour half life, small potency
bumetanide
loop diuretic- most potent, when furosemide is maxed out, a banned agent for athletes who need to meet a certain weight, renal elimination
torsemide
loop diuretic- 3 and 1/2 hour half life because it undergoes extensive metabolism, metabolic elimination, 2nd largest potency
ethacrynic acid
loop diuretic, 100% bioavailability, 1 hour half life, renal elimination
HCTZ
thiazide, eliminated renally, 70% bioavailability, 2.5 hour half life, least potent
chlorthalidone
thiazide, mostly renally eliminated, least potent, 47 hour half life (largest half life)
indapamide
thiazide, metabolic elimination, most potent, 65% bioavailability, 14 hour half life
metolazone
thiazide, more potent than chlorthalidone and HCTZ, less potent than indapamide, mostly renally excreted and a little biliary and metabolic, 8-14 hour half life
amiloride
collecting duct diuretic, longest half life, 15-25% bioavailability, most potent, diarrhea and headache
triamterene
collecting duct diuretic, 50% bioavailability, 4 hour half life, 10x less potent than triamterene, causes leg cramps and dizziness
eplerenone
collecting duct diuretic
spironolactone
collecting duct diuretic, 65% bioavailability, 1.6 hours half life, diarrhea gastritis, peptic ulcers, drowsiness/lethargy
diuretics effect on ECF volume and weight
decreases
pros of diuretics
decreases blood pressure, helps edema
cons of diuretics
too much of a decrease, SNS, RAAS
what does a diuretic do
decrease NaCl, decrease H2O
Excretion is greater than intake
Na excretion increases, Na stops going down and is a steady state,
excrete to much what is the consequence
hypoatremia
CA inhibitors site of action and MOA
site of action: proximal tubule
plays a role in bicarbonate reabsorption (Bicarbonate is tied to Na+)
these agents reduce Na+ by preventing reabsorption of bicarbonate - by preventing Na+ reabsorption, the water will follow H2O and so water will go out of the body with the HCO3- and Na+
What happens to k+ in CA inhibitors?
Increases excretion, RAAS System
What happens to urinary pH with CA inhibitors?
Urine becomes more basic- causes metabolic acidosis and decreases the pH (why some people take acetezolamide - they have acidosis)
Use of CA inhibitors
Glaucoma (aqueous humor in the eye has a lot of bicarbonate and topical formulation lowers the pressure causing less volume)
ICU treating metabolic alkalosis caused by excessive use of loop diuretics