Diurectics Flashcards
What hormones are made in the kidney ?
renin, EPO, prostaglandins and Calcitriol
what does the kidney metabolise ?
Vit D, Polypeptides (insulin) , drugs such as morphine
how does mannitol work ?
what is the main side effect?
increases the Osmolarity of the lumen moving more water into the lumen
hypernatremia
where do loop diuretics work on ? what receptor?
thick ascending limb
NK2Cl receptor
why do loop diuretics cause hypokalaemia ?
increased Na+ delivery late in tubule leads to incresed K+ loss from ENaC related Na+ absorption
what are the main side effects of Loop diuretics ?
hyponatremia , hypocalaemia, hypokalaemia and metabolic alkalosis
how do thiazides work ?
block Na+/Cl- in DCT. not as potent
what are the side effects of thiazides ?
hypercalaemia , hypokalaemia , metabolic alkalosis
what is the action of aldosterone on the kidney?
up regulation of ENaCa and Na/K/ATPase in principal cells of CD
what does amiloride do ?
blocks ENaC in the CD
what does spironolactone do ? how is it K+ sparing ?
blocks aldosterone receptor in CD which allows K+ not to be released via ROMK channels
what do carbonic anhydrase diuretics do ?
block NaHCO3- reabsorption in PCT
can lead to acidosis
How does alcohol and caffeine cause diuresis ?
alcohol suppresses ADH
increased GFR and decreased Tubular Na+ reabsorption
name 2 ADH antagonists
lithium - only water laves = hypernatremia
Tolvaptan - used in hyponatraemia
what are the general ADRs of diuretics?
hypovalaemia and hypotension
AKI
electrolyte disturbances
anaphylaxis
what are side effects of thiazides ?
Gout, hyperglyceamia, ED , hypercalaemia , Increases LDL and TG
What are side effects of frusemide ?
alkalosis , ototoxicity , Gout
what are the side effects if spironolactone ?
hyperkalaemia, impotence and gynaecomastia
what diuretics used in hypertension ?
Thiazide (as they can vasodilate)
spironolactone
what diuretics used in HF?
Loop and spironolactone
what diuretic used in liver disease?
spironolactone and loop
what diuretic used in nephrotic syndrome ?
loop diuretic
+/- thiazide or K+ sparing w/ K+ supplements
what is difference between primary and secondary hyperalodosterism ?
primary - low renin levels due to adrenal making too much aldosterone
secondary - high renin with hypotension due to body causing the adrenal glands to release too much aldosterone
what diuretic used in CKD ?
Loop diuretic - alkalosis and k+ excretion is good
avoid K+ Sparing
why can you build up a tolerance to diurectics in HF, Nephrotic syndrome and CKD ?
HF = Not enough blood circulating to deliver drug
Nephrotic = not enough protein to bind drug to
reduction in nephrons and OATs = CKD
Gut oedema can also stop absorption
what are the steps you should take in refractory oedema ?
check salt intake IV furosemide tritrate dose give repeated bolus need higher doses in HF
why do thiazides cause hypo natraemia and kalamia the most ?
they work on the top bit of the nephron on the DCT so less like lt to affect the conc gradient so less water is lost compared to loop diuretic
Name 3 nephrotoxic drugs
drugs shouldn’t be used in Renal dysfunction
Aminoglycosides - Gentamicin
IV Vancomyosin
Aciclovir
NSAIDs
ACE-i , diuretic, NSAIDs, metformin
what happens in renal artery stenosis to AA and EA?
AA- dilates due to prostacyclin
EA- Constricts , ANG2
What do NSAIDs and ACE-i do on the kidney ?
NSAIDs stop PGs = less dilation of AA
ACE-I stop ANG2 Which stops constriction
what drugs should you be careful with in CKD?
Digoxin , heparin , gentamicin , opiates , cyclosporin
what is the management of hyperkalaemia ?
Calcium gluconate - heart protection
insulin/dextrose
calcium resonium
what are the general ADRs of diuretics?
hypovalaemia and hypotension
AKI
electrolyte disturbances
anaphylaxis
what are side effects of thiazides ?
Gout, hyperglyceamia, ED , hypercalaemia , Increases LDL and TG
What are side effects of frusemide ?
alkalosis , ototoxicity , Gout
what are the side effects if spironolactone ?
hyperkalaemia, impotence and gynaecomastia
what diuretics used in hypertension ?
Thiazide (as they can vasodilate)
spironolactone
what diuretics used in HF?
Loop and spironolactone
what diuretic used in liver disease?
spironolactone and loop
what diuretic used in nephrotic syndrome ?
loop diuretic
+/- thiazide or K+ sparing w/ K+ supplements
what is difference between primary and secondary hyperalodosterism ?
primary - low renin levels due to adrenal making too much aldosterone
secondary - high renin with hypotension due to body causing the adrenal glands to release too much aldosterone
what diuretic used in CKD ?
Loop diuretic - alkalosis and k+ excretion is good
avoid K+ Sparing
why can you build up a tolerance to diurectics in HF, Nephrotic syndrome and CKD ?
HF = Not enough blood circulating to deliver drug
Nephrotic = not enough protein to bind drug to
reduction in nephrons and OATs = CKD
Gut oedema can also stop absorption
what are the steps you should take in refractory oedema ?
check salt intake IV furosemide tritrate dose give repeated bolus need higher doses in HF
why do thiazides cause hypo natraemia and kalamia the most ?
they work on the top bit of the nephron on the DCT so less like lt to affect the conc gradient so less water is lost compared to loop diuretic
Name 3 nephrotoxic drugs
drugs shouldn’t be used in Renal dysfunction
Aminoglycosides - Gentamicin
IV Vancomyosin
Aciclovir
NSAIDs
ACE-i , diuretic, NSAIDs, metformin
what happens in renal artery stenosis to AA and EA?
AA- dilates due to prostacyclin
EA- Constricts , ANG2
What do NSAIDs and ACE-i do on the kidney ?
NSAIDs stop PGs = less dilation of AA
ACE-I stop ANG2 Which stops constriction
what drugs should you be careful with in CKD?
Digoxin , heparin , gentamicin , opiates , cyclosporin
what is the management of hyperkalaemia ?
Calcium gluconate - heart protection
insulin/dextrose
calcium resonium
