Diuretics

Question 1

Two types of diuretics

Answer 1

Osmotic = only mannitol, raises osmotic pressure of kidney and draws water into it (only used for cerebral oedema)
Natriuretics = increase amount of sodium in urine

Question 2

Therapeutic uses

Answer 2

Heart failure = reduce ECV, reduce oedema and vasodilate to help bring ventricles back to normal range of starling curve
Hypertension = Reduce ECV and vasodilate

Question 3

Loop diuretics

Answer 3

Furosemide
Inhibit the NKCC transport of TAL
Less gradient for water reabsorption, so more excreted
Vasodilation
Side effects = hypotension (volume depletion), K+ loss, hypokalaemia

Question 4

Thiazide diuretics

Answer 4

Bendroflumethiazide
Less potent than loop diuretics
Inhibit the NCC on the distal tubule
Milder side effects, smaller loss of K+

Question 5

Problems with K+ ions

Answer 5

As more Na+ enters the lumen and is absorbed, potassium ions and protons are lost into the urine
Activates the JGA to reabsorb more Na+

Question 6

Osmotic diuretics

Answer 6

Mannitol
Filtered by glomerulus and increases osmolarity of filtrate
More water enters urine and is excreted
Osmotic activity in tubule diminishes fluid reabsorption

Question 7

Potassium sparing diuretics

Answer 7

Spironolactone = inhibitor of aldosterone (aldosterone causes more sodium absorbed)
Amiloride = blocks ENaC channels on CD

Question 8

CA inhibitor

Answer 8

Acetazolamide
More bicarbonate excreted with more water
inhibits bicarb absorption in PCT

Question 9

treatment for incontinece

Answer 9

muscarine antagonist

Question 10

treatment for outflow obstruction

Answer 10

alpha 1 antagonist