FA Renal Drugs Flashcards
Mannitol drug type
osmotic diuretic
Mannitol MOA
- increases tubular fluid osmolarity (plasma osmotic pressure) in PCT
- increases urine flow
- decreases intracranial/intraocular pressure
Mannitol Clinical Use
- Drug overdose
- Elevated ICP/IOP
Mannitol Toxicity
- Excessive plasma volume expansion
- Pulmonary congestion/edema
- Dehydration
Mannitol C/I
- Anuria
- Heart failure
Acetazolamide drug type
Carbonic anhydrase inhibitor
Acetazolamide MOA
- Inhibits carbonic anhydrase in brush border and intracellularly in PCT
- No H+ produced → No Na+/H+ exchg → Na+ stays in lumen
- Self-limited NaHCO3 diuresis
- Decrease in total body HCO3- stores
- Alkalinizes urine
Carbonic Anhydrase does what?
- Catalyzes CO2 + H2O → H2CO3
- H2CO3 spontaneously decomposes to HCO3- + H+
- Required for Na+/H+ exchg in PCT, NaHCO3 reabsorption from PCT, and H+ secretion in collecting duct
Acetazolamide Clinical Use
- Glaucoma (reduce aq humor production)
- Metabolic alkalosis
- Altitude sickness
- Pseudotumor cerebri
Acetazolamide Toxicity
- HypERchloremic metabolic acidosis [ACIDazolamide]
- Increased Cl- reabsorption to compensate for decreased bicarb reabsorption
- Acidification of CSF → Paresthesias, other CNS effects
- NH3 toxicity
- Sulfa allergy
- Blood cell deficiencies
Sulfa Diuretics
FAT:
- Furosemide
- Acetazolamide
- Thiazides
Mannitol location of action
PCT
Acetazolamide location of action
PCT
Loop Diuretic Drugs
- Furosemide
- Bumetanide
- Torsemide
- Ethacrynic Acid
Loop Diuretic location of action
Thick Ascending LOH
Loop Diuretic drug type
Sulfonamide (except Ethacrynic Acid)
Loop Diuretic MOA
- Inhibits Na+/K+/2Cl- transporter (out of lumen)
- Abolishes hypertonicity of medulla
- Prevents concentration of urine
- Stim PGE release → afferent arteriole dilation
- Inhibited by NSAIDs
NSAIDs inhibit which diuretics?
Loop diuretics (PGE)
Loop Diuretics increase excretion of which ions?
- Na+
- K+
- Cl-
- Ca2+
- Mg2+
Loop Diuretics clinical use
- Edematous states (HF, cirrhosis, nephrotic synd, pulm edema)
- HTN
- Hypercalcemia
Loop Diuretics Toxicity
OHH DANG!
- Ototoxicity (worsened by aminoglycosides)
- HypOkalemia
- HypOcalcemia
- Dehydration
- Allergy (sulfa)
- Nephritis (interstitial)
- Gout (hyperuricemia)
Preferred diuretics in pts w/renal impairment?
Loop Diuretics
Acetazolamide increases excretion of which ions?
HCO3-
Only non-sulfa Loop Diuretic
Ethacrynic Acid
Diuretic used in pts w/sulfa allergy
Ethacrynic Acid
Ethacrynic Acid drug type
Phenoxyacetic acid derivative
Thiazide Diuretic drugs
- Hydrochlorothiazide
- Chlorthalidone
Thiazide Diuretic location of action
Early DCT
Thiazide Diuretic MOA
- Inhibit NaCl reabsorption in early DCT
- Decrease diluting capacity of nephron
- Decrease Ca2+ excretion (PTH effect)
Thiazide Diuretic Clinical Use
- HTN
- HF
- Edema
- Idiopathic hypERcalciuria
- Nephrogenic diabetes insipidus
- helps concentrate urine
- Osteoporosis
- Calcium stones