Diuretics Flashcards
Mannitol
Osmotic diuretic
All segments
Decreases Na, K, Cl, Ca, P, Mg
Indicated in cases of cerebral edema and ICP
Contraindicated in CHF
Furosemide
Loop diurectic
Thick ascending loop of henle
Decreases Na, K, Cl, Ca, P, Mg
Used for pulmonary edema due to CHF
Effective at low GFR
Increases K, Ca, and Mg excretion
Increases renal vasodilation, renin secretion, and venous capacitance
Hydrochlorothiazide
Thiazide diuretic
Distal tubule
Decreases Na, K, Cl, Ca, P, Mg
Used with loop diuretic to treat refractory heart failure
Not effective at low GFR
Spironolactone
Aldosterone antagonist
Distal tubule and collecting duct
Decrease Na, Cl, and Ca; increase K
Not used for acute CHF, used for primary hyperaldosteronism or cirrhosis
Poor diuretic
Triamterene
Distal diuretic
Distal tubule and collecting duct
Decrease Na, Cl; increase Ca and K
Acetylzolamide
Carbonic anhydrase inhibitor
Proximal tubule
Decrease Na, K, Cl, and P
Weak diuretic used for glaucoma
Why use diuretics?
Treatment of fluid excess
To improve excretion of waste and toxins
Promote urine flow like in kidney failure
How do diuretics work?
Pathologic
ADH system dysfunctions
Pressure natriuresis
Osmotic diuresis
How do diuretics work?
Therapeutic
Exogenous loading of salt and water
Administration of poorly absorbed solutes
Pharmacologic inhibition of tubular reabsorption mechanisms
Where do osmotic diuretics work
Loop of henle descending
Where do carbonic anhydrase inhibitors work
Proximal convoluted tubule
Where do loop diuretics work
Ascending loop of henle/ straight distal tubule
Where do thiazine diuretics work
Distal convoluted tubule
Where do K sparing diuretics work
Collecting duct
Which diuretic does not act from the luminal side of the tubular cells
Spironolactone
