hypertension

Question 1

Give three examples of ACE inhibitors

Answer 1

• Ramipril
• Lisinopril
• Perindopril

Question 2

What is the primary mechanism of action of ACE inhibitors?

Answer 2

• Inhibits ACE
• Prevents conversion of Ang I to Ang II

Question 3

What is the drug target of ACE inhibitor?

Answer 3

ACE

Question 4

What are the main side effects of ACE inhibitor?

Answer 4

• Cough
• Hypotension
• Hyperkalaemia (care with K+ supplements or K+ sparing diuretics)
• Foetal injury (avoid in pregnant women)
• Renal failure (in renal artery stenosis patients)
• Urticaria (hives)/angioedema (swelling under skin)

Question 5

What must happen for ACE inhibitors to have an effect?

Answer 5

Most ACE inhibitors (not lisinopril) are prodrugs so require hepatic activation to have an effect

Question 6

What must be monitored when prescribing ACE inhibitors?

Answer 6

eGFR and serum K+

Question 7

What are two examples of calcium channel blockers?

Answer 7

• Amlodipine
• Felodipine

Question 8

What is the primary mechanism of action of calcium channel blockers?

Answer 8

• Block L-type calcium channels, predominantly on vascular smooth muscle
• Results in decrease in calcium influx and downstream inhibition of myosin light chain kinase and prevention of cross-bridge formation
• Resultant vasodilation reduces peripheral resistance

Question 9

What is the drug target of calcium channel blockers?

Answer 9

L type calcium channel

Question 10

What are the main side effects of calcium channel blockers?

Answer 10

• Ankle oedema
• Constipation
• Palpitations
• Flushing/headache

Question 11

What Ca2+ channel blockers demonstrate a higher degree of vascular selectivity?

Answer 11

Dihydropyridine type calcium channel blockers demonstrate a higher degree of vascular selectivity

Question 12

Give two examples of thiazide or thiazide-like diuretics

Answer 12

• Bendro-flumethiazide (thiazide)
• Indapamide (thiazide-like)

Question 13

What is the primary mechanism of action of thiazide/thiazide-like diuretics?

Answer 13

• They block Na+ Cl- cotransporter in early DCT
• Therefore Na+ and Cl- reabsorption is inhibited
• As a result the osmolarity of the tubular fluid increases, decreasing the osmotic gradient for water reabsorption in collecting duct

Question 14

What is the drug target of thiazide/thiazide-like diuretics?

Answer 14

sodium/chloride cotransporter

Question 15

What are the main side effects of thiazide/thiazide-like diuretics?

Answer 15

• Hypokalaemia
• Hyponatraemia
• Metabolic alkalosis (increased H+ excretion)
• Hypercalcaemia
• Hyperglycaemia (hyperpolarised pancreatic beta cells)
• Hyperuricaemia

Question 16

What happens after 1-2 weeks of treatment of thiazide diuretics?

Answer 16

Drugs lose diuretic effects. Continuing antihypertensive action appears to be due to vasodilating properties (more pronounced for thiazide-like diuretics)

Question 17

What are some examples of angiotensin receptor blockers?

Answer 17

• Losartan
• Irbesartan
• Candesartan

Question 18

What is the primary mechanism of action of angiotensin receptor blockers?

Answer 18

These act as insurmountable (non-competitive) antagonists at AT1 receptor (found on kidneys and on vasculature)

Question 19

What is the drug target of angiotensin receptor blockers?

Answer 19

Angiotensin receptor

Question 20

What are the main side effects of angiotensin receptor blockers?

Answer 20

• Hypotension
• Hyperkalaemia (care with K+ supplements and K+ sparing diuretics)
• Foetal injury (avoid in pregnant women)
• Renal failure (in patients with renal artery stenosis)

Question 21

How would you compare angiotensin receptor blockers to ACE inhibitors?

Answer 21

• Not as effective antihypertensives as ACEi
• Losartan and candesartan are prodrugs so require hepatic activation to have effects