Pharm - Diuretics Flashcards
Mannitol
Sketchy: Tall man
MOA:
Osmotic diuretic
USES:
- Drug Overdose
- Reduction of elevated intracranial pressure
- Reduction of intraocular pressure
ADVERSE EFFECTS:
Pulmonary edema
Dehydration
Contraindicated in heart failure
Acetazolamide
Sketchy: race car track
MOA:
Inhibits carbonic anhydrase (CA) at the proximal tubule (Recall: Na+/H+ exchanger will excrete H+ into lumen to combine with HCO3- to produce H2CO3, which can be broken down by CA into H2O and CO2 and reabsorbed; Acetazolamide makes it so that HCO3- is stuck in the lumen so H+ cannot be recycled to be used again in the Na+/H+ exchanger)
EFFECTS:
Natriuresis
Diuresis
USES:
- Glaucoma
- Urinary alkalization (increased solubility of uric acid and cysteine - decreased stone formation in gout and cysteinuria)
- Metabolic alkalosis (due to increased bicarb excretion)
- Altitude sickness
- Pseudotumor cerebri (idiopathic intracranial hypertension)
ADVERSE EFFECTS:
- Renal tubular acidosis
- Paresthesias
- Sulfa allergy
Furosemide
Sketchy: furious kid in the roller coaster
MOA:
Inhibits Na+/K+/2Cl- (NKCC) cotransporter in the thick ascending loop
EFFECTS:
- Decreases hypertonicity of medulla, preventing concentration of urine in the descending loop
- Also induce the expression of COX-2, increasing PGE, causing vasodilation of afferent arteriole and enhancing diuretic action
- Increase Ca2+ excretion (loss of the positive lumen potential which usually pushes Ca2+ and other cations out of the lumen and into the interstitium; positive potential usually caused by K+ being reabsorbed and then diffusing back into the lumen)
USES:
- Edematous states (HF, cirrhosis, nephrotic syndrome, pulmonary edema)
- HTN
- Hypercalcemia
ADVERSE EFFECTS:
- Hypokalemia (due to effects later on in nephron)
- Dehydration
- Sulfa allergy
- Ototoxicity
- Interstitial nephritis
- Gout
- Action of drug inhibited by NSAIDs
Ethacrynic acid
Sketchy: Ethics sign near roller coaster
MOA:
Non-sulfa inhibitor of Na+/K+/2Cl- cotransporter in the ascending loop
EFFECTS:
USES:
Diuretic effects in patients allergic to sulfa drugs
ADVERSE EFFECTS:
- Hypokalemia (due to effects later on in nephron)
- Dehydration
- Sulfa allergy
- Ototoxicity (worse than with Acetazolamide)
- Gout
- Action of drug inhibited by NSAIDs
Thiazides (Hydrochlorathiazide, Chlorthalidone, Metolazone)
Sketchy: pasty thighs
MOA:
Inhibits Na+/Cl- cotransporter in the early distal convoluted tubule
EFFECTS:
- Decreased Na+ and Cl- absorption
- Increased Ca2+ absorption (decreased intracellular Na+ will stimulate the basolateral Na+/Ca2+ exchanger, causing Ca2+ to be pushed into the interstitial space)
USES:
- HTN
- HF
- Idiopathic hypercalciuria (prevention of calcium stone)
- Nephrogenic DI
- Osteoporosis (due to enhanced calcium reabsorption)
ADVERSE EFFECTS: Hypokalemic metabolic acidosis Hyponatremia Hyperglycemia Hyperlipidemia Hyperuricemia (gout) Hypercalcemia Sulfa allergy
Spironolactone
Sketchy: inspector with spiral notebook
MOA:
K+ sparing duiretic; directly antagonizes mineralocorticoid receptor
EFFECTS:
- Decreased activity of apical ENaC channel (decrease Na+ absorption)
- Decreased activity of apical K+ channel (decreased K+ excretion)
- Decreased activity of H+ ATPase in alpha-intercalated cell (decreased H+ excretion)
USES:
- Hyperaldosteronism
- Hypokalemia
- HF
- Hepatic ascites
- Androgen excess in PCOS (spirinolactone blocks 17-a-hydroxylase)
ADVERSE EFFECTS:
- Hyperkalemia (arrhythmias)
- Gynecomastia (spirinolactone can antagonize androgen receptors)
Eplerenone
Sketchy: teacher with apple
MOA:
K+ sparing duiretic; directly antagonizes mineralocorticoid receptor
EFFECTS:
- Decreased activity of apical ENaC channel (decrease Na+ absorption)
- Decreased activity of apical K+ channel (decreased K+ excretion)
- Decreased activity of H+ ATPase in alpha-intercalated cell (decreased H+ excretion)
USES:
- Hyperaldosteronism
- Hypokalemia
- HF
- Hepatic ascites
ADVERSE EFFECTS:
-Hyperkalemia (arrhythmias)
Triamterene
Sketchy: tangerine cart
MOA:
K+ sparing duiretic; Blocking of ENaC channel in the collecting duct
EFFECTS:
-Decreased activity of apical ENaC channel (decrease Na+ absorption)
USES:
-HF
ADVERSE EFFECTS:
-Hyperkalemia (arrhythmias)
Amiloride
Sketchy: almond cart
MOA:
K+ sparing duiretic; Blocking of ENaC channel in the collecting duct
EFFECTS:
-Decreased activity of apical ENaC channel (decrease Na+ absorption)
USES:
- HF
- Lithium-induced nephrogenic DI
ADVERSE EFFECTS:
-Hyperkalemia (arrhythmias)