3. Diuretics Flashcards
What do carbonic anhydrase inhibitors cause?
Loss of NaHCO3
Hypokalaemic metabolic acidosis
What are carbonic anhydrase inhibitors used for?
Glaucoma
Mountain sickness
What is the role of mannitol in the nephron?
Loss of water
Reduced intracellular volume
Hypernatraemia risk
What do loop diuretics lead to?
Loss of Na and water
Hypokalaemic metabolic alkalosis
Increased Ca2+ loss
What do thiazide diuretics lead to?
Loss of Na and water
Hypokalaemic metabolic acidosis (due to increased activity of ENaC in collecting duct)
Increased Ca2+ reabsorption
What is the role of tolvaptan?
ADH antagonists - aquaretics
Used to treat hyponatraemia
Stop aquaporin channels inserting into collecting duct
What are some other substances that have diuretic action?
Alcohol - inhibits ADH release
Caffeine - increases GFR and decreases tubular Na+ reabsorption
What are some generic adverse drug reactions to diuretics?
Hypovolaemia and hypotension - activates RAAS, can lead to AKI
Electrolyte disturbance
Metabolic abnormalities
Anaphylaxis/photosensitivity rash
What are some specific drug reactions of thiazides?
Gout Hyperglycaemia Erectile dysfucntion Increased LDL and TG Hypercalcaemia
What are some specific drug reactions to furosemide?
Ototoxicity
Alkalosis
Increased LDL and TG
Gout
What are some specific dug reactions to spironolactone?
Hyperkalaemia
Impotence
Painful gynaecomastia
What is a specific drug reaction to bumetanide?
Myalgia
What can happen if ACEi and K+ sparing diuretics are used together?
Increased hyperkalaemia -> cardiac problems
What can happen if aminoglycosides and loop diuretics are given together?
Ototoxicity and nephrotoxicity
What can happen if digoxin and thiazide/loop diuretics are given together?
Hypokalaemia -> increased digoxin binding and toxicity
