Diuretics And Renal Pharmacology Flashcards
On what part of the nephron do carbonic anhydrase inhibitors work?
Proximal convoluted tubule
How do carbonic anhydrase inhibitors elicit their actions
They prevent reabsorption of bicarbonate from the renal tubule which results in decreased activity of apical sodium-hydrogen exchanger so causes diuretics due to retention f sodium in the renal tubules
When are carbonic anhydrase inhibitors contraindicated
Hepatic cirrhosis
Are carbonic anhydrase inhibitors Aquaretic, Natriuretic or Diuretic?
Diuretic
What warnings are associated with carbonic anhydrase inhibitors?
Metabolic acidosis
Kidney stones due to alkaline urine
Hypokalaemia
What is Mannitol?
An osmotic agent
Where do osmotic agents elicit their actions?
PCT and decending loop of Henley
How do osmotic agents such as mannitol work?
Inhibit resorption of water and sodium thus increasing the osmolarity of blood and renal filtrate
What is risk of osmotic agents?
Hypernatraemia risk
What are SGLT2 inhibitors
They inhibit sodium-glucose transport protein 2 to lower blood sugar
Which diuretic drug class causes decreased body weight, decreased blood pressure, decreased plasma glucose, decreased plasma Uri acid and decreased glomerular hyperfiltration?
SGLT2 inhibitors
SGLT2 inhibitors act on which part of the nephron?
Proximal tubular cells
Where do loop diuretics act on the nephron?
Ascending limb of Henle
Loop diuretics are better than thiazides in patients with what?
Impaired kidney function
On what protein do loop diuretics act and to what effect?
They act on the NKCC2 ( Na+ K+, 2Cl-) symporter to inhibit reabsoprtion causing loss of water and sodium
What electrolyte disturbance could be induced by a loop diuretic such as furosemide?
Hypokalaemia metabolic acidosis
What are the Adverse drug reactions associated with the loop diuretic furosemide?
Ototoxicity
Alkalosis
Increased LDL and triglyceride
Gout
Which transporter is the target of thiazides?
Sodium chloride transporter
Where do thiazides act on the nephron?
Distal convoluted tubule
How do thiazides work?
The inhibit the Na-Cl transporter.
The transporter usually pulls NaCl from the lumen of the DCT, but its inhibition means that NaCl and water remain in the lumen so more urine is made per day
What electrolyte disturbance can be caused by thiazides?
Hypokalaemia metabolic acidosis
Do thiazide increase or decrease calcium resorption?
Increase
Which drug class is a competitive antagonist for aldosterone
Potassium sparing diuretic
How do potassium diuretics work?
Competitive antagonist with aldosterone
Prevent sodium reabsorption
Prevent K+ and H+ ion secretion in the late distal tubule and collecting duct
What ADRs are associated with thiazides?
Gout Hyperglycaemia Erectile dysfunction Increased LDL Increased triglyceride Hypercalcaemia
Name a potassium sparing diuretic
Spironolactone
What ADR’s are associated with potassium sparing diuretic?
Hyperkalaemia
Impotence
Painful gymaecomastia
To what drug class does Tolvaptan belong?
An ADH antagonist - Aquaretic
Which drug class is used to treat hyponatraemia and prevent cyst enlargement in adult polycystic kidney disease
ADH antagonists
ADH antagonists word at which receptor?
V2 receptor - it blocks it
Which metal has the same activity as ADH antagonists as a side effect?
Lithium
How does alcohol act as a diuretic?
Inhibits ADH release
How does caffeine act as a diuretic?
Increases GFR and decreased tubular Na+ reabsorption
What is an ADR of Bumetanide
Myalgia
Which diuretics would you use for hypertension?
Thiazide diuretics
Spironolactone
Loop diuretics
Which drugs would traditionally be used in heart failure?
Loop diuretics
Spironolactone
Which drugs would traditionally be used in decompensated liver disease?
Spironolactone
Loop diuretics
Which drugs would traditionally be used in the treatment of nephrotic syndrome
Loop diuretics - big doses needed
+/- thiazides
+/- potassium sparing diuretics / potassium supplements
Which drugs would be used in CKD
Loop diuretics
What 3 things must be present for diuretics to be delivered to the renal tubule?
Blood flow to proximal tube
Proximal tube must be functioning to transport furosemide across
Thick ascending limb must be intact to respond to furosemide
Decribe Barrters and Gitelmans syndromes
Autosomal recessive disorder
Defect in thick ascending limb
Causes alkalosis and hypokalaemia and results from no function
How does bartters and gitelmans syndrome differ from Liddles syndrome
Bartters - reduced or no function
Liddles - increased function
