Potassium sparing diuretics Flashcards
Name 3 potassium sparing diuretics.
Amiloride, trimeterene and spironolactone.
How do the potassium sparing diuretics amiloride and trimeterene work?
Inhibits sodium reabsorption by blocking Na+ channels.
increased Na, Cl and water secretion. Decreased K secretion.
Where do these work?
collecting tubule
What are the side effects of amiloride and trimeterene?
Hyperkalaemia, may cause acidosis.
Which drug has a more rapid onset?
Trimeterene has a more rapid onset and is shorter acting than amiloride.
What is the mechanism of action of spironolactone?
Competitive antagonist of aldosterone and thus reduces Na absorption. Decreased K absorption.
What are the clinical uses of spironolactone?
Hypertension. Primary and secondary hyperaldosteronism (e.g. Conns syndrome).
