Angiotensin Receptor Blocker

Question 1

What are examples of angiotensin receptor blockers?

Answer 1

• Losartan
• Candesartan
• Irbesartan

Question 2

When are ARBs indicated for use?

Answer 2

• Hypertension
• CHF
• IHD
• Diabetic nephropathy
• CKD

Question 3

How do ARBs work?

Answer 3

Block the action of angiotensin II on the AT1 receptor - reduces peripheral vascular resistance (afterload), which lowers blood pressure; dilates the efferent glomerular arteriole, which reduces intraglomerular pressure and slows the progression of CKD. It also reduces aldosterone levels, which promotes sodium and water excretion.

Question 4

What are important adverse side effects of ARBs?

Answer 4

• Hypotension
• Hyperkalaemia
• Renal failure

Question 5

What patients are particularly at rink of renal failure when given ARBs?

Answer 5

Those with renal artery stenosis

Question 6

What drugs can ARBs interact with?

Answer 6

• Spironolactone
• Potassium suuplements
• NSAIDs- increase renal failure risk

Question 7

How are ARBs taken?

Answer 7

Orally

Question 8

What dose of losartan would you start someone on for treating hypertension?

Answer 8

25 mg Once daily - then titrate as needed to 100 mg once daily

Question 9

What dose of losartan would you start someone on if they had heart failure?

Answer 9

12.5 mg once daily - increase weekly to 150 mg daily if needed

Question 10

What dose of candersartan would you start someone on with hypertension?

Answer 10

8mg - increase weekly to 32 mg maximum

Question 11

What dose of candesartan would you start someone on with heart failure?

Answer 11

4mg once daily - increased at intervals of 2 weeks to maximum tolerated dose

Question 12

When is it best for individuals to take first dose of ARB?

Answer 12

Before bed - avoid symptomatic hypotension

Question 13

When monitoring ARB use, what biochemical changes would alert you to stop giving them?

Answer 13

• Creatinine > 30% increase
• eGFR >25% decrease