ACE inhibitors

Question 1

Give some examples of ACE inhibitors

Answer 1

Ramapril and isonopril

Question 2

How do ACE inhibitors work?

Answer 2

Block the action of ACE preventing Angiotensin I –> Angiotensin II
Angiotensin II can not have its affects so:
- Vasdoliation –> Reduced PVR –> Reduced afterload
- Reduction in aldosterone secretion –> Reduced water and sodium retention –> reduced venous return –> reduced preload
- Vasodilation particularly at the efferent glomerular arteriole

Question 3

What are the common uses for ACE inhibitors?

Answer 3

1. Hypertension: first line in those <55 who are not afro-carribean
2. Chronic heart failure - symptoms and prognosis
3. IHD - prevent CV events
4. Diabetic nephropathy and CKD with protein urea

Question 4

What are the contra-indications of using ACE inhibitors?

Answer 4

1. Renal artery stenosis
2. AKI
3. Pregnant Women
4. Breast feeding women
5. Angioedema

Question 5

When should ACE inhibitors be used with caution?

Answer 5

CKD - monitor renal functions and Lower the dose

Question 6

What are the common side effects of ACE inhibitors?

Answer 6

Hypotension after first dose
Hyperkalamia
Renal failure 
Dry cough
Angioedema and other anaphylactoid reactions

Question 7

Why do you get a dry cough with ACE inhibitors?

Answer 7

Increase levels of bradykinin as it is not broken down by ACE

Question 8

What are the common interactions with ACE inhibitors?

Answer 8

Potassium sparing diuretics
Potassium supplements
Other diuretics
NSAIDs - renal failure

Question 9

How are ACE inhibitors excreted?

Answer 9

Hepatic metabolism

Question 10

When should patients ideally take their first dose of an ACE inhibitor and ARBs?

Answer 10

Before bed to prevent the effects of hypotension

Question 11

What information should you give patients before starting Ace inhibitors?

Answer 11

Avoid NSAIDs

Come back for regular monitoring of renal function

Question 12

Why do you start low dose and treat up with Ace inhibitors and ARBS?

Answer 12

Profound hypotension may occur following the first dose of an ACE inhibitor, particularly in patients on other diuretics, such as loop diuretics, and those with restricted salt and water intake. You should start at a low dose and titrate up gradually to find the best effects

Question 13

When monitoring renal function what should you look out for?

Answer 13

creatinine concentration should not rise by more than 30%eGFR should not fall by more than 25%
potassium concentration should not rise above
6.0 mmol/L.
If any of these limits are exceeded, stop the drug
(Same for ARBS)

Question 14

Why are ACEi not recommended for afro-carribeans?

Answer 14

The incidence of angioedema related to ACE inhibitor treatment is five times higher (about 1%) in black people of African or Caribbean origin.