Diuretics

Question 1

What are the side effects of carbonic anhydrase inhibitors?

Answer 1

Metabolic acidosis
Hypokalaemia
Renal stones

Question 2

What are the side effects of osmotic diuretics?

Answer 2

Hypernatraemia

Allergic reaction

Question 3

What are the side effects of Loop diuretics?

Answer 3

Hypokalaemia
Raised TAG and LDL
Ototoxicity 
Alkalosis
Gout

Question 4

What type of diuretic can be used to treat hypercalcaemia?

Answer 4

Loop diuretics

Question 5

What are the side effects of thiazide diuretics?

Answer 5

Hypercalcaemia
Raised TAG and LDL
Erectile dysfunction
Hyperuciaemia -> gout 
Hypokalaemia

Question 6

What are the side effects of Spironolactone?

Answer 6

Painful gynaecomastia
Impotence
Hyperkalaemia

Question 7

What are the side effects of ADH antagonist, Lithium?

Answer 7

Hypernatramia

Liver function compromised

Question 8

Which diuretics are recommended in hypertension?

Answer 8

Thiazide - vasodilation

Spironolactone

Question 9

Which diuretics are indicated for heart failure?

Answer 9

Loop - relieve symptoms from fluid overload

Spironolactone - reduce mortality

Question 10

Which diuretics are recommended for liver disease?

Answer 10

Spironolactone

Loop

Question 11

Which diuretics are recommended for nephrotic syndrome?

Answer 11

Loop

Question 12

Which diuretics are recommended in CKD?

Answer 12

Loop +/- thiazide (not thiazide alone)

Question 13

Which diuretics should be avoided in CKD and why?

Answer 13

K+ sparing - already risk of K+ retention in kidney disease.

Question 14

Which diuretic for glaucoma?

Answer 14

CA inhibitor

Question 15

Which diuretic for cerebral oedema?

Answer 15

Mannitol - osmotic

Question 16

What is the risk of ACE-I + K+ sparing diuretic?

Answer 16

Hyperkalaemia

Question 17

What is the risk of gentamicin + loop diuretic?

Answer 17

Nephrotoxicity + ototoxicity

Question 18

What is the risk of digoxin + thiazide/loop?

Answer 18

Thiazide/loop induce hypokalaemia which increases digoxin binding -> digoxin toxicity.

Question 19

What is the risk of steroids + loop/thiazide?

Answer 19

Hypokalaemia

Question 20

What is the effect of lithium + loop?

Answer 20

Loop diuretic decreases lithium levels

Question 21

What is the effects of lithium + thiazide?

Answer 21

Thiazide increases lithium concentration

Question 22

What is the risk of beta blocker + thiazide?

Answer 22

Hyperglycaemia
Hyperlipidaemia
Hyperuricaemia

Question 23

What is the risk of carbamezepine + thiazide?

Answer 23

Hyponatraemia

Question 24

What 4 things might contribute to diuretic resistance?

Answer 24

1. Gut function - oedema from nephrotic syndrome
2. Circulation
3. Albumin - delivery to kidney. Hypoalbuminaemia decreases delivery.
4. Kidney function - PT for transport of diuretic into lumen via OAT.

Question 25

Name some nephrotoxic drugs.

Answer 25

Gentamicin
Vancomycin
NSAIDs
Aciclovir

Question 26

Which diabetic drug can cause acidosis if renal function is compromised?

Answer 26

Metformin

Question 27

Explain why thiazides lead to hypokalaemia and hyponatraemia whereas loop diuretics do not.

Answer 27

Thiazides - increased delivery of NaCl, RAAS activated and ADH released. Hypertonic medulla causes increased water reabsorption and plasma dilution.

Loop - also cause RAAS activation and ADH release but ADH less effective as tonicity of intersitium decreased.

Question 28

What 3 steps are key in the management of hyperkalaemia?

Answer 28

1. Calcium gluconate - stabilise myocytes
2. Dextrose and Insulin - K+ uptake
3. Diuretic or calcium resonium - K+ excretion

Question 29

What ECG changes indicate worsening hyperkalaemia?

Answer 29

Tall T waves
P waves flatten/dissapear
PR lengthened
Wide QRS
Sine wave pattern
Aystole