Renal Medications Flashcards
What class of diuretics do not require access to the tubular lumen for effective action:
Mineralocorticoid receptor antagonists
What do osmotic pressure gradients determine?
Determine intracellular and extracellular fluid distribution
What do Starling forces determine?
Determine intravascular vs. extravascular distribution (plasma volume vs. interstitial fluid volume)
What are the general classes of diuretics?
- Osmotic diuretics
- Carbonic anhydrase inhibitors
- Loop diuretics
- Thiazides/thiazide-like diuretics
- K+ sparing diuretics
- Aquaretics
Where do osmotic diuretics access the lumen?
Glomerular filtration
Which diuretics gain entrance into the lumen by organic acid transport?
Loop diuretics
Thiazides
Acetazolamide
What are the loop diuretics?
Furosemide
Bemetanide
Torsemide
Where in the nephron tubule does a majority of K+ depletion occur?
Convoluted tubule
What are the two mineralocorticoid receptor antagonists?
Spironolactone
Eplerenone
What are the uses of K+ sparing diuretics?
Hyperaldoseteronism
Hypokalemia
HFrEF
Resistant HTN
What is the MOA of V2 receptor antagonists?
Block AVP action in the late DT and CD
Inhibit urine concentration by preventing AVP-stimulated AQP2 insertion into luminal membrane of principal cells (inhibit water abstraction in DT & CD)
Describe the concept diminished “ceiling” natriuretic effect?
It is often called a high-ceiling diuretic because it is more effective than other diuretics. Furosemide decreases the sodium, chloride, and potassium reabsorption from the tubule. Subsequently, these ions are retained in the renal tubule and presented to the distal nephron.
How do diuretics differ within their class?
Pharmacodynamically equivalent - they differ in potency, not in efficacy
Pharmocokinteically they are different in bioavailability, elimination route, and cost
Agent selection based on PK and cost!
What loop diuretic is preferred for Rx due to being low cost and efficacious?
Furosemide
What electrolyte imbalance is most commonly seen in loop diuretic use?
Hypokalemia
True or False: All loop diuretics are pharmacologically similar when administered at equivalent doses
True
If a patient on a maximal dose of a loop diuretic without effect, should another loop diuretic be trialed?
No, there is no evidence to suggest that another loop would be effective because they are equivalent at similar effective doses