Diuretics Flashcards
Where do thiazide diuretics act?
DCT- inhibit sodium chloride transport.
What are the side effects of thiazide diuretics?
Thirst Hypokalaemia Impotence Need to urinate Increased blood glucose Increased uric acid (gout) Increased cholesterol
What are thiazide diuretics used for?
Hypertension
Chronic mild heart failure, if renal function normal.
Where do loop diuretics act?
Ascending LOH, to inhibit NaCl transport (NKCC cotransporter)
What are the main uses of loop diuretics?
Heart failure (chronic cardiac failure and acute LV failure)
Hypertension with chronic renal failure (but not normally used for HTN)
For fluid balance in renal disease (CRF and nephrotic syndrome)
NB: give IV in acute heart failure.
Can give with thiazide diuretics in resistant HF.
Where do potassium sparing diuretics act?
DCT. Inhibit Na/K exchange.
What is the specific action of amiloride?
Block the Na/K exchanger.
What is the specific action of spironolactone?
Inhibit the action of aldosterone on the Na/K exchanger.
What is spironolactone used for?
Heart failure Secondary hyperaldosteronism (e.g. chronic liver disease)
What is acetazolamide?
Carbonic anhydrase inhibitor. Used in altitude sickness.
What is mannitol used for?
Cerebral oedema
What is demeclocycline and what is it used for?
A tetracycline antibiotic. Physiologically, this works by reducing the responsiveness of the collecting tubule cells to ADH. Used for inappropriate ADH secretion.
What is Tolvaptan?
ADH receptor blocker (V2 receptors).
Used for SIADH.
What drugs cause renal impairment?
Diuretics (pre-renal) ACE inhibitors Penicillamine Gentamicin Amphotericin Lithium NSAIDs
What drugs cause renal impairment?
Diuretics (pre-renal)
ACE inhibitors (dilatation of efferent arteriole)
Penicillamine (causes glomerulonephritis and proteinuria)
Gentamicin (damage tubules)
Amphotericin (damage tubules)
Lithium (interferes with effect of ADH in CD. Causes diabetes insipidus)
NSAIDs (damages interstitium- interstital nephritis)
