renal - drugs Flashcards
nephron anatomy (and cortex vs medulla)
glomerulus (cortex) –> proximal convoluted tubule (cortex and medulla) –> descending limb loop of Henle (medulla) –> loop of henle (medulla) –> ascending limb of henle (medulla and cortex) distal convoluted tubule (cortex) –> collecting duct
diuretics - group of drugs
- mannitol
- Acetazolamide
- loop diuretics
- thuazide
- K+ sparing diuretics
mannitol - mechanism of action
acts on proximal convoluted tubule and on descending loop of Henle
- osmotic dieuretic: increases tubular fluid osmolarity –> increased urine flow
- decreased intracranial/intraocular pressure
mannitol - clinical use
- drug overdose
2. elevated intracranial/intraocular pressure
mannitol - adverse effects
- pulmonary edema
- dehydration
CONTRAINIDCATED IN ANURIA, HF, CEREBRAL HEMORRHAGE
mannitol - contraindicated in
- anuria
- HF
3, Cerebral hemorrhage
acetazolamide - mechanism of action
carbonic anhydrase inhibitor in PCT –> self limited NaHCO3 diuresis and low total body HCO3- stores
acetazolamide - location of action
- PCT (cytoplasm and brush border)
2. other tissues (eye, brain)
acetazolamide - clinical use
- Glaucoma
- urinary alkalinization
- metabolic alkalosis
- pseudotumor cerebri
- altitude sickness
altitude sickness?
illness caused by ascent to high altitude, characterized by hyperventilation, nausea, and exhaustion resulting from shortage of oxygen
acetazolamide - adverse effects
- proximal renal tubular acidosis
- Paresthesias
- NH3 toxicity
- sulfa allergy
Loop diuretics are divided to (and drugs)
Sulfonamide loop diuretic –> a. Furosemide b. bumetanide c. torsemide
Nonsulfonamide loop diuretics –> ethacrynic acid
Sulfonamide loop diuretics - drugs
a. Furosemide
b. bumetanide
c. torsemide
Sulfonamide loop diuretics - mechanism of action
- inhibit contrasport system (Na+/K+/2CL-) of thick ascending limb of loop of Henle –> Abolish hypertonicity of medulla, preventing concentration of urine, increase Ca2+ and Mg2+ excretion
- stimulates PGE release (vasodilatory effect on afferent arteriole)
Sulfonamide loop diuretics - clinical use
- edematous states (HF, cirrhosis, nephrotic syndrome, pulmonary edem)
- hypertension
- hypercalcemia
Sulfonamide loop diuretics - adverse effects
- ototoxiicty
- Hypokalemia
- Dehydration
- Allergy (sulfa)
- metabolic alkalosis
- interstitial nephritis
- gout
Nonsulfonamide loop diuretics - drugs
ethacrynic acid
Nonsulfonamide loop diuretics (ethacrinic acid) - mechanism of action
inhibit contrasport system (Na+/K+/2CL-) of thick ascending limb of loop of Henle
Nonsulfonamide loop diuretics (ethacrinic acid) - clinical use
diuresis in patient with allergic to sulfa drug
Nonsulfonamide loop diuretics (ethacrinic acid) - side effects
similar to Sulfonamide loop diuretics but more OTOTOXIC and no sulfa): 1. ototoxiicty 2. Hypokalemia
- Dehydration 4. metabolic alkalosis
- interstitial nephritis 6. gout
Nonsulfonamide loop diuretics (ethacrinic acid) - side effects are similar to Sulfonamide loop diuretics but more
ototoxic
chronic loop diuretic use may mimic
Bartter syndrome
Thiazide diuretics - drugs
- Hydrochlorothiazide
- chlorthalidone
- metolazone
Thiazide diuretics - mechanism of action
Inhibit NaCL reabsorption in early DCT –> low diluting capacity of nephron and low Ca2+ excretion
Thiazide diuretics - clinical use
- hypertension
- HF
- Idiopathic hypercalciuria
- Nephrogenic diabetes insibitus
- osteoporosis
- chronic calcium stone formation