K SPARING DIURETICS

Question 1

Examples

Answer 1

1. Amiloride - E.g Co-amilofruse (e.g.
   Furosemide and Amiloride)
   Co-Amilozide (e.g.
   Hydrochlorothiazide with Amiloride)
   - Weak diuretic
2. Triamterene
   - Weak diuretic
3. Aldosterone antagonists
   - Potent diuretic

Question 2

Example of Aldosterone antagonists

Answer 2

• Spironolactone
• Eplerenone

Question 3

What are some of the indications for Spironolactone?

Answer 3

• Oedema
• Ascites (caused by cirrhosis of the liver)
• Moderate to severe heart failure
• Oedema in Congestive heart failure
• Resistant hypertension

Question 4

Contraindications for spironolactone

Answer 4

Hyperkalaemia
Addisons disease

Question 5

What are the side effects of
spironolactone?

Answer 5

1. HYPERkalaemia
2. Menstrual disorders - post-menopausal bleeding
3. Gynaecomastia - enlargement of a man’s breasts, due to hormone imbalance
4. Breast pain
5. Alopecia

Question 6

What are the similarities and difference between
Aldosterone antagonists (e.g.
Spironolactone) and Loop/Thiazide-like diuretics in terms of how they effect electrolytes?

Answer 6

• Loop/Thiazide-like diuretics
  cause hyponatraemia and
  Hypo-Kalaemia (decrease sodium, decrease potassium)
• Aldosterone antagonists (e.g.
  spironolactone) like loop/
  thiazide-like diuretics
  cause hyponatraemia, but they
  cause HYPERrkalaemia
  (decrease sodium, INCREASE potassium)

Question 7

Can Spironolactone be used in renal impairment?

Answer 7

• Avoid in acute renal insufficiency or severe impairment
• Monitor plasma-potassium concentration (high risk of Hyperkalaemia in renal impairment)

Question 8

Monitoring parameters in spironolactone

Answer 8

• Monitor electrolytes, discontinue if hyperkalaemia
  occurs

Question 9

Some interactions with spironolactone

Answer 9

1. ACE-inhibitors/ARBs
   - Increase risk of
   HYPERkalaemia
   - Hypotension
2. Other antihypertensive
   drugs
   - Risk of hypotension
3. Other drugs that cause
   hyperkalaemia
   - e.g. Heparins, Ciclosporins, K supps
4. NSAIDs
   - Attenuate (decrease) effects of Diuretics and increase risk of nephrotoxicity
5. Lithium
   - reduce clearance of Lithium (i.e. increase concentration)
6. Digoxin
   - Increases risk digitalis

Question 10

Which diuretics make the urine look slightly blue in some lights?

Answer 10

Triamterene
- weak potassium sparing diuretic