Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
41 Cards in this Set
- Front
- Back
|
What is the purpose of diuretics?
|
Increase the rate of urine flow and increase the rate of Na+ excretion usually as NaCl
|
|
|
What are some examples of cardiovascular diuretics?
|
digitalis (digoxin), phosphodiesterase inhibitors (aminophylline, inamrinone, milrinone)q
|
|
|
What is the clinical use of cardiovascular diuretics?
|
Treatment of edema associated with congestive heart failure
|
|
|
Physological diuretics include:
|
water and NaCl
|
|
|
What effect does additional water have on the body?
|
Inhibits the release of ADH
|
|
|
What is the clinical use of water as a physiological diuretic?
|
used in compensated chronic interstitial nephritis of dogs
|
|
|
When is NaCl used as a physiological diuretic
|
in sheep, calves, and cats with urolithiasis
|
|
|
What are some examples of osmotic diuretics?
|
mannitol, urea, glycerin, isosorbide
|
|
|
What is the mechanism of action for osmotic diuretics?
|
acts at the loop of henle and PCT to interefere with transport mechanisms and increase urinary excretion of metabolites thereby decreasing medullary tonicity.
|
|
|
What are the clinical uses of osmotic diuretics?
|
local edema only: cerebral edema, acute glaucoma, acute renal failure, mobilized edema fluid, drug overdose
|
|
|
What are some examples of a loop or high ceiling diuretic?
|
furosemide, bumetanide, ethacrynic acid
|
|
|
What is the mechanism of action of drugs like furosemide?
|
inihibits the Na/K/2Cl- symporter and paracellular reabsorption of Na, Ca, Mg
|
|
|
Which class of diuretics is the most efficacious and why?
|
Loop Diuretics are the most efficacious because ~25% of filtered Na+ is reabsorbed at the ascending loop
|
|
|
How does hypokalemia and thus systemic alkalosis develop with administration of loop diuretics?
|
Hypokalemia and resultant systemic alkalosis is caused by the increased delivery of Na+ in the distal tubule and collecting duct. This increases the potential difference of the membrane and facilitates K+ excretion through K+ channels in luminal membrane of the principle cells. There are also H+ secretion by intercalated cells into the lumen. RAAS stimulation also contributes.
|
|
|
What are the therapeutic uses for loop diuretics like furosemide?
|
acute pulmonary edema, pulmonary congestion, generalized edema associated iwth congestive heart failure, chronic renal failure, and liver cirrhosis.
increased intracranial pressure and udder edema, exercise induced pulmonary hemorrhage in horses |
|
|
Which class of diuretics is used to tx exercise induced pulmonary hemorrhage in horses?
|
loop diuretics- furosemide
|
|
|
Which class of diuretics would be used to threat life-threathening hyponatremia in conjuction with hypertonic saline?
|
loop diuretics because they inhibit the kidney from producing concentrated urine
|
|
|
What are some adverse effects of loop diuretics?
|
ototoxicity, hypokalemia, hypomagnesemia, acute hypovolemia, hypotension, cardiac arrhythmia, hyperglycemia, hyperuricemia, systemic alkalosis, hypersensitivity
|
|
|
What are the pharmacokinetics of furosemide?
|
orally or IV
onset is rapid, duration is short |
|
|
What are some examples of thiazide diuretics?
|
hydrochlorothiazide, chlorothiazide
|
|
|
What is the mechanisms of action for thiazide diuretics?
|
inhibit the Na+-Cl= symporter in DCT- inhibits tubular reabsorption of Na/Cl
|
|
|
Compare the efficacy of thiazide diuretics to loop diuretics.
|
Thiazide diurectics have a lower efficacy compared with loop diurects because of their site of action. Loop diuretics act on the ascending loop of henle where 25 % of Na is reabsorbed wherease thiazide diuretics work in the DCT where only 5% is reabsorbed
|
|
|
Which two diuretic classes cause hypokalemia and systemic alkalosis?
|
loop diuretics and thiazide diuretics
|
|
|
What the major clinical uses of thiazide diuretics?
|
tx of hypertension, nephrogenic diabetes insipidus, calcium nephrolithiasis, osteoporosis, udder edema,
|
|
|
What are the adverse effects of thiazide diuretics?
|
electrolyte imbalance (hypnatremia, hypokalemia, hypmagnesemia), but less than loop. Hyperglycemia, hypersensitivity reactions in patients allergic to sulfonamides
|
|
|
What are the pharamcokinestics of thiazide diuretics?
|
orally, absorption is slow/incomplete, binds to plasma proteins, excreted in kidneys
|
|
|
What are some examples of potassium sparing diuretics?
|
spironolactone, triamterene, amiloride
|
|
|
What is the mechanism of action for spironolactone?
|
competitively blocks aldosterone resutls in excretion of NaCl and diureses as well as retention of K+ and H+
|
|
|
Rank the diuretics in terms of efficacy:
|
Loop>thiazide>potassium sparing
|
|
|
What are the therapeutic uses of spironolactone?
|
diuretic, treatment of 1 and 2 hyperaldosteronism
|
|
|
What are the adverse effects of spironolactone?
|
hyperkalemia, systemic acidosis, effects reproduction
|
|
|
What considerations do we have to make for spironolactone?
|
it has a slow onset (2-3 days), long duration, only mild diuretic effect
|
|
|
What is the mechanism of action for the potassium sparing diuretics triamterene and amiloride?
|
blocks epithelial Na+ channels in DCT and collecting duct.
|
|
|
what are the therapeutic uses of triamterene or amiloride?
|
treatment of hypokalemia, hypomagnesemia
|
|
|
What drugs make up the carbonic anhydrase inhibitors?
|
acetazolamide, methazolamide, dorzolamide, brinzolamide
|
|
|
How do Carbonic anhydrase inhibitors work?
|
reversible inhibiton of carbonic anydrase which exchanges H for Na at PTC
|
|
|
Therapeutic uses of carbonic anhydrase inhibitors?
|
treatment of chronic glaucoma, udder edema
|
|
|
Adverse effects of carbonic anhydrase inhibitors:
|
mild systemic acidosis, hypokalemia, hyperglycemia
|
|
|
What is the drug that is used to diagnose Diabetes insipidus?
|
ADH helps us differentiate between Central and Nephrogenic DI
If central caused by ADH def and we'll see change, if neprhogenic no response |
|
|
`Which drugs would we use to treat central Diabetes insipidus?
|
Desmopressin via nasal drops
|
|
|
Which drug would we use to treat nephrogenic diabetes insipidus?
|
thiazide diuretic
|
