Diuretics

Question 1

What are diuretics?

Answer 1

= increase the volume and output of urine –> diuresis

• loop diuretics
• thiazide diuretics
• potassium sparing diuretics

Question 2

Define Natriuresis

Answer 2

= excretion of sodium in the urine

Question 3

MOA of diuretics

Answer 3

= inhibit the reabsorption of sodium at different sites in the renal tubules (cause more sodium to be excreted)

• increase osmotic pressure in renal tubers and reduce passive reabsorption of water
• amount of diuresis produced depends on amount of sodium resorption inhibited

Question 4

MOA loop diuretics and example

Answer 4

• inhibits sodium potassium chloride pump in the ascending loop of Henle
  e. g. frusemide

Question 5

Side effects of loop diuretics?

Answer 5

• potential electrolyte disturbances e.g. hypokalaemia, hyponatraemia
• may increase blood uric acid and precipitate gout
• may increase BGL
• May produce urinary frequency and urgency

Question 6

Indications of loop diuretics?

Answer 6

• oedema associated with Heart failure

- renal impairment

Question 7

Contradictions of loop diuretics

Answer 7

• hyperglycaemia - increase BGL

Question 8

Interactions with loop diuretics

Answer 8

• adrenaline

- K depleating agents (laxatives)

Question 9

Nursing practice points for loop diuretics

Answer 9

• start low dose
• monitor renal function
• monitor weight and electrolytes

Question 10

MOA for Spironolactone (potassium sparing diuretics)

Answer 10

= copetes with aldosterone and inhibits stimulant effects of aldosterone on sodium potassium exchange (late distal)

• aldosterone pulls sodium and water in and pumps potassium out

Question 11

Adverse reactions of Thiazide?

Answer 11

• Hypokalaemia/natremia
• increased blood uric and
• hyperglycaemia
• urinary urge and frequency increase

Question 12

Adverse reactions of potassium sparing diurtics?

Answer 12

• hyperkalaemia
• hypotraemia
• hepototoxicity

Question 13

Interactions with potassium sparing diurectics

Answer 13

• ACE inhibitors

- antihypertensives

Question 14

Nursing practice points of potassium sparing diuretics

Answer 14

• weak diuretic

- check renal function and potassium levels

Question 15

Effects of diuretics on sodium excretion?

Answer 15

= all may produce hyponatremia

Question 16

effects of diuretics on potassium excretion?

Answer 16

Loop diuretics and thiazides
= increase potassium excretion - may produce hypokalaemia

Spironolactone
= decreased potassium excretion - may produce hyperkalaemia