Angiotensin Receptor Blockers

Question 1

Give some example of ARBS

Answer 1

Losartan, Candesartan

Question 2

How do ARBS work?

Answer 2

Block angiotensin II from binding to the AT1 receptor
Angiotensin II can no longer have its effects therefore there is a:
- Increase in vasodilation –> reduced PVR –> Reduced after load
- Reduced aldosterone –> Decrease in sodium and water retention –> reduced venous return –? Reduced pre load
- Dilation of efferent glomerular arteriole

Question 3

What are ARBs commonly used for?

Answer 3

1. Hypertension : first line in those <55 who are not afro-caribean
2. Chronic Heart Failure
3. Ishcaemic heart disease: prevent CV event
4. Diabetic nephropathy and CKD with proteinurea

Question 4

What are the contraindications of using ARBs?

Answer 4

1. Renal artery stenosis
2. AKI
3. Preganant women
4. Breast-feeding women

Question 5

When should ARBs be used with caution?

Answer 5

1. In CKD as have an effect on kidneys so lower the doe and monitor renal function

Question 6

What are the side effects of ARBs

Answer 6

Hypotension (on first dose)
Hyperkalamia
Renal Failure
*Less likely to get Angioedema compared to ACEi

Question 7

What are the common interactions with ARBs?

Answer 7

Potassium sparing diuretics
Potassium supplements
Other diuretics - hypotension
NSAIDS - renal failure

Question 8

How are ARBs eliminated?

Answer 8

Hepatic metabolism

Excreted in urine and faeces

Question 9

What do you need to warn your patents before putting them on ARBs?

Answer 9

They need renally monitored

Try to avoid NSAIDs