ACE Inhibitors

Question 1

Give 5 examples of ACE inhibitors

Answer 1

• Captopril
• Enalapril
• Lisinopril
• Perindopril
• Ramipril

Question 2

What is the mechanism of action of ACE inhibitors?

Answer 2

They inhibit the conversion of angiotensin I to angiotensin II by blocking angiotensin converting enzyme (ACE)

Question 3

What does blocking angiotensin II do?

Answer 3

Angiotensin II is a potent vasoconstrictor, so blocking its production causes blood vessels to relax and dilate

Question 4

How are ACE inhibitors administered?

Answer 4

PO

Question 5

What can ACE inhibitors be combined with in a single pill?

Answer 5

Can be used in combination drugs with calcium channel blockers or diuretics

Question 6

What is the advantage of combination drugs include ACEi?

Answer 6

It can make it easier for patients who take multiple medications to control their BP

Question 7

What are the indications for ACEi?

Answer 7

• Hypertension
• CHD
• Ischaemic heart disease
• Diabetic nephropathy

Question 8

Describe the role of ACEi in hypertension?

Answer 8

First line in Caucasian people and those aged <55

Question 9

Describe the role of ACEi in CHD?

Answer 9

First line

Question 10

Describe the role of ACEi in ischaemic heart disease?

Answer 10

One of the 5 drugs indicated post-MI

Question 11

When can ACEi not be used in diabetic nephropathy?

Answer 11

When there is renal impairment

Question 12

Describe the role of ACEi in diabetic nephropathy?

Answer 12

Slows progression of renovascular disease

Question 13

What are the cautions and contraindications to ACEi?

Answer 13

• Renal artery stenosis or known renal impairment
• Known hypersensitivity
• Hyperkalaemia
• Women who are pregnant

Question 14

Why should you avoid using ACEi in renal artery stenosis/known renal impairment?

Answer 14

ACEi reduces glomerular filtration

Question 15

Why should you avoid using ACEi in women who are pregnant?

Answer 15

Teratogenic, and can damage fetal renal function and BP control

Question 16

When should you seek specialist advice before using ACEi?

Answer 16

• Aortic stenosis
• Mitral stenosis
• Hypertrophic cardiomyopathy

Question 17

Why should you seek specialist advice before using ACEi in patients with aortic stenosis, mitral stenosis, and hypertrophic cardiomyopathy?

Answer 17

ACEi can cause vasodilation, which can cause blood pressure reduction in those with fixed cardiac outputs

Question 18

Can you use ACEi when breastfeeding?

Answer 18

You can use some but not others

Question 19

What monitoring should be done with ACEi?

Answer 19

Check U&Es prior to starting treatment and 1-2 weeks after, and on increasing dose

Question 20

Why do you need to check U&Es prior to starting treatment with ACEi?

Answer 20

To establish baseline renal function

Question 21

What other drugs might interact with ACEi?

Answer 21

• Nephrotoxic drugs
• K-sparing diuretics and K supplements
• Other drugs affecting the renin-angiotensin-aldosterone system

Question 22

Give 4 examples of nephrotoxic drugs

Answer 22

• NSAIDs
• Lithium
• Metformin
• Diuretics

Question 23

What might result from interaction between ACEi’s and nephrotoxic drugs?

Answer 23

Increased risk of AKI

Question 24

What might result from the interaction between ACEi and K-sparing diuretics/K supplements?

Answer 24

Increased risk of hyperkalaemia

Question 25

What might result from the interaction between ACEi and other drugs affecting the RAAS system?

Answer 25

Increased risk of hypotension, hyperkalaemia, and renal impairment compared to use of single drugs

Question 26

What are the common side effects of ACEi's?

Answer 26

- Dry cough - 1st dose hypotension - Hyperkalaemia

Question 27

Why do ACEi's cause a dry cough?

Answer 27

Because ACEi inhibit bradykinin metabolism and free bradykinins cause bronchoconstriction

Question 28

What is a less common but very important side effect of ACEi?

Answer 28

Angio-oedema

Question 29

What pneumonic (is that spelt right) can be used to remember the side effects of ACEi's?

Answer 29

CAPTOPRIL ``` C - cough A - angio-oedema/anaphylaxis P - palpitations T - taste disturbance O - orthostatic hypotension P - potassium elevated R - renal impairment I - impotence L - leucocytosis ```

Question 30

What needs to be talked about in patient counselling when starting ACEi?

Answer 30

- Dry cough - 1st dose hypotension - NSAIDs - Surgery - Pregnancy - Angio-oedema/allergic reactions

Question 31

What needs to be talked about regarding dry cough in ACEi counselling?

Answer 31

If the patient develops a dry cough within the first months of starting ACEi, they should report this to their GP and be switched to an ARB

Question 32

What needs to be talked about regarding 1st dose hypotension in ACEi counselling?

Answer 32

If the patient is at risk of 1st dose hypotension, suggest the dose is taken at night

Question 33

What needs to be talked about regarding NSAIDs in ACEi counselling?

Answer 33

Should be advised not to take NSAIDs, e.g. ibuprofen, whilst taking ACEi

Question 34

What needs to be talked about regarding surgery in ACEi counselling?

Answer 34

ACEi are normally stopped on the day of surgery, unless told otherwise

Question 35

What needs to be talked about regarding pregnancy in ACEi counselling?

Answer 35

If the patient becomes pregnant, ACEi should be stopped immediately and alternatives offered

Question 36

What needs to be talked about regarding angio-oedema/allergic reactions in ACEi counselling?

Answer 36

If swelling of the face, eyes, lips, or tongue develops, of if breathing difficulties occur, stop drug and call ambulance