Name 2 diuretics that act in the PCT
mannitol and acetazolamide
What acid base status would result from a person going on acetazolamide?
acidosis (metabolic) because they are losing their NaHCO3
What is the most common sulfonamide loop diuretic?
Where does acetazolamide act in the nephron?
In what 2 ways do loop diuretics cause diuresis?
1) By inhibiting the NKCC pump in the TALH they cause a loss of hypertonicity in the renal medulla, thus, you cannot concentrate urine. 2) The stimulate PGE production which dilates the afferent arteriole and increases GFR
What AE is shared by spironolactone and cimetidine?
development of gynecomastia
What is the MOA of acetazolamide?
It is a carbonic anhydrase inhibitor, therefore, NaHCO3 is lost in the urine, this causes acidosis
3 indications for thiazides
HTN, idiopathic hypercalciuria, nephrogenic diabetes insipidus
What 2 diuretics cause alkalosis and why?
Loops and thiazides. This is predominately secondary to K loss, this pulls H in from plasma in exchange for K? Also, the volume contraction turns on RAAS which further causes H loss
Which K sparing diuretics are competitive antagonists of ENaC?
What are the indications (3) for loop diuretics?
Edematous states, hypercalcemia, and hypertension
What are the two MOA's of potassium sparing diuretics?
1) competitive aldosterone inhibitor in cortical collecting tubules 2) Sodium Channel blocker (ENaC) in cortical collecting tubule
Which type of diuretic is actually contraindicated in congestive heart failure?
Which diuretic is used to treat pseudotumor cerebri?
What are the AE of thiazide diuretics (5)?
Sulfa allergy and hyperGLUC = Hyper -Glycemia, -Lipidemia, -Uricemia, -Calcemia
Which diuretic would be best for a hypercalcemic patient? Hypocalcemic?
Loop diuretics cause loss of Ca; Thiazides increase serum Ca
Which K sparing diuretics are competitive aldosterone antagonists?
Spironolactone and eplerenone
Which side effects are not present in ARBs that ACE-inhibitors cause?
Cough and Angioedema because ARBs do not increase bradykinin
Where does mannitol act in the nephron?
How is the chemical makeup of ethacrynic acid different from furosemide?
Ethacrynic acid is from phenoxyacetic acid whereas furosemide is from sulfonamides
Which diuretic has the most endocrine AE?
Spironolactone, can cause gynecomastia
What effect do ACE-I have on cardiac tissue in CHF?
Somehow prevent unfavorable remodeling of heart tissue
Which 2 diuretics may cause acidosis and why?
1) Carbonic anhdyrase inhibitors (Acetazolamide) because it increases secretion of HCO3 2) K sparing diuretics because it blocks aldosterones ability to secrete H, and the excess K is exchanged for H at the cellular level, further increasing the acidosis
What are the indications for K sparing diuretics?
Hyperaldosteronism, CHF, and K depletion
What are the indications for mannitol?
Decreasing an increase in intracranial pressure and for drug overdose
What is acetazolamide indicated for (5)?
Glaucoma, urinary alkalinization, metabolic alkalosis, altitude sickness (respiratory alkalosis), and pseudotumor cerebri
In whom is mannitol contraindicated?
Anuric patients and CHF
What is the MOA of thiazide diuretics?
Inhibit NaCl reabsorption by the distal tubule, this blocks the diluting capability of the nephron
Why do ACE inhibitors cause hyperkalemia?
Because there is no stimulation of aldosterone which would cause K secretion
Why do ACE inhibitors increase serum creatinine?
because they decrease the GFR
What are the adverse effects of mannitol?
pulmonary edema and dehydration
What is the MOA of mannitol?
An osmotic diuretic, it increases the osmolarity of the renal TUBULE, thereby increasing urine flow
Which renal drugs are highly teratogenic?
Which diuretic is a phenoxyacetic acid derivative? Significance?
Ethacrynic acid? Other loop diuretics are from sulfa drugs, so ethacrynic acid can be given to a pt with sulf allergy
Which type of diuretic is most likely to lead to a cardiac arrhythmia and why?
K sparing diuretic because of the potential for hyperkalemia
What drug increases tubular fluid osmolarity thereby producing an increase in urine flow?
Which diuretics can be used to treat nephrogenic diabetes insipidus?
Which diuretics are best for osteoporotic patients?
Thiazides because increase calcium reabsorption
What are the plasma renin levels of a person on ACE-inhibitors?
increased due to loss of negative feedback
Where in the nephron is the increased calcium reaborption with thiazides taking place?
Paracellular route in LOH and PCT; HOWEVER, thiazides act on the DCT
Name 3 types of diuretics that can cause sulfa allergy
acetazolamide, hydrochlorothiazide, and loop diuretics (ethacrynic acid is safer)
What are the AE (6) of loop diuretics?
Ototoxicity, Hypokalemia, Dehydration, sulfa Allergy, interstitial Nephritis, Gout (OH DANG = mnemonic)
Which drugs can inhibit loop diuretics? Why?
NSAIDs; part of the effect of the loop diuretic involves the release of PGE to dilate afferent arteriole and increase GFR, NSAIDs would block that
In whom are ACE inhibitors contraindicated because they will precipitate renal failure?
Bilateral renal artery stenosis, as they will further decrease GFR