Drugs Flashcards
MOA of mannitol
osmotic diuretic - increased tubular fluid osmolarity, producing increase urine flow, decreases intracranial/intraocular pressure
- uses : drug overdose, and increased ICP/IOP
ADE of mannitol
pulmonary edema, dehydration,
- CI in anuria and CHF
MOA of Acetazolamide
CA inhibitor causing self limited NaHCO3 diuresis and decreases total body HCO3- stores
- uses: glaucoma, urinary alkalinization, metabolic alkalosis, altitude sickness, pseudotumor cerebri
ADE of acetazolamide
Hyperchloremia metabolic acidosis, parethesias, NH3 toxicity, sulfa allergy
MOA of loop diuretic (furosemide, ethancrynic acid, torsemide)
inhibitis NaK2Cl cotransporter in thick ascending limb
- abolishes hypertonicity of medulla, preventing concentration of urine
- stimulates PGE release (vasodilatory effect on affferent arteriole)
- increases Ca excretion (loops lose Ca)
ADE of furosemide
OH DANG - otoxicity, hypokalemia, dehydration, allergy (sulfa), nephritis (interstitial), gout
use of ethacrynic acid
Diuresis in pts allergic to sulfa drugs. It’s a phenoxyacetic acid derivative.
- NEVER use to treat gout
MOA of HCTZ
Thiazide diuretic - inhibits NaCl reabsorption in early distal tubule.
- decreases diluting capacity of nephron, decreases Ca excretion
- uses: HTN, CHF, idiopathic hypercalciuria, nephrogenic DI, osteoporosis (saves Ca)
ADE of HCTZ
-GLUC
hypokalemia metabolic alkalosis, hyponatremia
- hyperGlycemia, hyperLipidemia, hyperUricemia, hyperCalcemia
- sulfa allergy
MOA of Spironolacton and eplerenone
competitive aldosterone receptor antagonists in cortical collecting tubule
MOA of triamterene and amiloride
block eNa Channels in CCT
ADE of K sparing diuretics
Hyperkalemia (can lead to arrhythmias)
Endocrine effects w/ spironolactone (gynecomastia and antiandrogen effects)
Diuretics and effect on urine NaCl
all increase urine NaCl except acetazolamide, serum NaCl may decrease as a result
Diuretics and effect on urine K
- increases w/ loop/thiazides
serum K may decrease as a result
Diuretics and effects on blood pH
- decrease (acidemia) - CA inhibitors and K sparing diuretics
- increase (alkalemia) - loop and thiazides
mechanism via which loops/thiazides causes blood alkalemia
- volume contraction - increases ATII = increases Na/H exchange in PT = increase HCO3- reabsorption
- K loss leads to K exiting all cells in exchange for H entering cells
- low K state, H is exchanged for Na in cortical collecting tubule = alkalosis and paradoxical aciduria
Diuretics and effects on urine Ca
- increase in loop b/c of decreased paracellular Ca reabsorption
- decrease w/ thiazide - enhanced paracellular Ca reabsorption in DT
MOA of ACE inhibitors
- decreases ATII and GFR by preventing constriction of efferent arterioles.
- levels of renin increase, prevent inactivation of bradykinin (potent vasodilator)
ADE of ACE inhibitor
Cough, Angioedema, Teratogen (renal malformations), increase Creatinine, Hyperkalemia, Hypotension
- CI in C1 esterase inhibitor deficiency
- avoid in bilateral renal artery stenosis b/c it will further decrease GFR and lead to renal failure
MOA of ARBs
ATII receptor blockers
- no increase in bradykinin so no cough or angioedema
MOA of CCB
block voltage dependent L type calcium channels of cardiac and SM = decrease contractility
- Vascular SM think dihydropyridine
- Heart think verapamil > dilitazem
What are dihydropyridine CCB’s used for?
- HTN
- Angina - including Prinzmetal
- Raynaud
What are the non-dihydropyridine CCB’s used for?
- HTN
- Angina
- Atrial fibrillation/flutter
What is Nimodipine used for?
Subarachnoid hemorrhage - prevents cerebral vasospasm