Cardiac drugs

Question 1

Examples of loop diuretics

Answer 1

Furosemide and bumetanide

Question 2

Loop diuretics mechanism of action

Answer 2

Act by inhibiting the Na-K-Cl cotransporter (NKCC) in the thick ascending limb of the loop of Henle, reducing the absorption of NaCl.

Question 3

What are the indications for use of loop diuretics?

Answer 3

1. heart failure: both acute (usually intravenously) and chronic (usually orally)
2. resistant hypertension, particularly in patients with renal impairment

Question 4

Side effects of loop diuretics

Answer 4

o	hypotension
o	hyponatraemia
o	hypokalaemia, hypomagnesaemia
o	hypochloraemia alkalosis
o	ototoxicity
o	hypocalcaemia
o	renal impairment
o	hyperglycaemia 
o	gout

Question 5

ACE inhibitors mechanism of action

Answer 5

1. inhibit the conversion angiotensin I to angiotensin II

2. ACE inhibitors are activated by phase 1 metabolism in the liver

Question 6

Side effects of ACE inhibitors

Answer 6

1. cough
2. angioedema: may occur up to a year after starting treatment
3. hyperkalaemia

Question 7

Contraindications of ACE inhibitors

Answer 7

 pregnancy and breastfeeding - avoid
 renovascular disease - may result in renal impairment
 aortic stenosis - may result in hypotension
 hereditary of idiopathic angioedema
 specialist advice should be sought before starting ACE inhibitors in patients with a potassium >= 5.0 mmol/L