diuretuc Flashcards
(8 cards)
MANNITOL, UREA, GLYCERIN, ISOSORBIDE
Class: Osmotic Diuretics
Mechanism:
Freely filtered at the glomerulus but not reabsorbed in the nephron
Increase osmolarity in the proximal convoluted tubule (PCT) and Loop of Henle (LoH)
Draw water from surrounding tissues into the tubular lumen by osmosis
Mannitol reduces cerebral edema and intracranial pressure, also lowers intraocular pressure
Uses:
Cerebral edema, intraocular pressure, maintenance of urine flow, elimination of toxic substances
Side Effects:
Transient increase in ECF volume, left ventricular failure, nausea, vomiting, hyponatremia
Notes:
Osmotic diuretics mainly excrete water, with Na, K, and Cl excretion being secondary due to solvent drag
Increased urine flow helps prevent tubular obstruction
FUROSEMIDE, BUMETANIDE, TORASEMIDE
Class: Loop Diuretics
Mechanism:
Inhibit Na/K/2Cl symporter in the thick ascending limb of the LoH
Disrupt the renal gradient necessary for water reabsorption in the collecting duct
Leads to excretion of large volumes of dilute urine
Uses:
Pulmonary edema (due to left ventricular failure)
Hypertension, hypercalcemia (increased renal excretion of calcium)
Rapid diuresis when needed
Side Effects:
Hypokalemia, metabolic alkalosis, ototoxicity, hyperuricemia, hypotension, hypovolemia, hypomagnesemia
Monitoring:
Monitor electrolytes and renal function
HYDROCHLORTHIAZIDE, BENDROFLUMETHIAZIDE
Class: Thiazide Diuretics
Mechanism:
Inhibit Na/Cl symporter in the distal convoluted tubule (DCT), reducing Na and Cl reabsorption
Mild diuresis, reducing intravascular volume and lowering blood pressure
Increases calcium reabsorption in the DCT (risk of hypercalcemia)
Uses:
Mild to moderate edema
Historically used for hypertension, but less common now
Side Effects:
Hypokalemia, hypercalcemia, hyperlipidemia, hyperuricemia
Monitoring:
Monitor electrolytes, blood pressure, glucose levels
INDAPAMIDE, CHLORTHALIDONE, METOLAZONE
Class: Thiazide-Like Diuretics
Mechanism:
Structurally different but act at the same site as thiazides
Longer duration of action and less prone to hypokalemia
Uses:
Hypertension (due to longer half-life)
Side Effects:
Postural hypotension, hyperglycemia, hypokalemia, electrolyte imbalances
Notes:
Stronger vasodilatory effect compared to thiazides
Milder hypokalemia
AMILORIDE, TRIAMTERENE
Class: Potassium-Sparing Diuretics - Na Channel Blocker
Mechanism:
Act on DCT and collecting duct, blocking epithelial sodium channels (ENaC)
Reduces sodium reabsorption, leading to mild diuresis and reduced potassium excretion
Uses:
Adjunct to other diuretics (thiazide or loop) to mitigate K loss
Side Effects:
Hyperkalemia (especially in renal impairment), kidney stones, GI disturbances, rashes, metabolic acidosis
SPIRONOLACTONE, EPLERENONE
Class: Potassium-Sparing Diuretics - Aldosterone Antagonist
Mechanism:
Block aldosterone receptors in the DCT and collecting duct
Prevent Na/KATPase overexpression, reducing Na reabsorption and K excretion
Uses:
Heart failure (reduces mortality)
Resistant hypertension (adjunct therapy)
Primary hyperaldosteronism, polycystic ovary syndrome (PCOS)
Post-MI
Side Effects:
Hyperkalemia, gynecomastia, menstrual irregularities (due to anti-androgenic effects)
Monitoring:
Monitor potassium and renal function
CHLORMERODIN, MERCAPTOMERIM SODIUM, MERALLURIDE
Class: Mercurial Diuretics
Mechanism:
Act by promoting water and electrolyte excretion through kidney tubules
Historically used for diuresis, less commonly used now due to toxicity risks
