Pharma - Hypertension

Question 1

List 4 common types of hypertensives.

Answer 1

→ ACE inhibitors
→ Calcium channel blockers
→ Thiazides or Thiazide-like diuretics
→ Angiotensin receptor blockers

Question 2

List 3 examples of ACE inhibitors.

Answer 2

→ Ramipril
→ Lisinopril
→ Perindopril

Question 3

What is the mechanism of action for ACE inhibitors?

Answer 3

→ Inhibit the angiotensin converting enzyme.
→ Prevent the conversion of
angiotensin I to angiotensin II by ACE.

Question 4

What is the drug target for ACE inhibitors?

Answer 4

ACE

Question 5

What are the main side effects of ACE inhibitors?

Answer 5

→ Cough
→ Hypotension
→ Hyperkalaemia (care with K+ supplements or K+-sparing diuretics)
→ Foetal Injury (AVOID IN PREGNANT WOMEN)
→ Renal failure (in patients with renal artery stenosis)
→ Urticaria / Angioedema

Question 6

What is a pro-drug?

Answer 6

drug that requires hepatic activation to generate metabolites needed to therapeutic effect

Question 7

Which of the ACE inhibitors are pro-drugs?

Answer 7

→ ramipril

→ perindopril

Question 8

What must be closely monitored when prescribing ACE inhibitors?

Answer 8

→ eGFR

→ serum potassium

Question 9

List 2 examples of Calcium channel blockers.

Answer 9

→ Amlodipine

→ Felodipine

Question 10

What is the mechanism of action of a calcium channel blocker?

Answer 10

→ Block L-type calcium channels – predominantly on vascular smooth muscle.
→ results in a decrease in calcium influx, with downstream inhibition of myosin light chain kinase and prevention of cross-bridge formation
→ resultant vasodilation reduces peripheral resistance.

Question 11

What is the drug target of calcium channel blockers?

Answer 11

→ L-type calcium channels

→ on vascular smooth muscle

Question 12

What are the main side effects of Calcium channel blockers?

Answer 12

→ Ankle oedema
→ Constipation
→ Palpitations
→ Flushing/Headaches

Question 13

Which type of calcium channel blockers demonstrate higher degree of vascular selectivity?

Answer 13

dihydropyridine

Question 14

List 2 examples of thiazide or thiazide-like diuretics?

Answer 14

→ thiazide = Bendro-flumethiazide

→ thiazide-like diuretics = Indapamide

Question 15

What is the mechanism of action of thiazide or TLD?

Answer 15

→ They block the Na+, Cl- co-transporter in the 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 the collecting duct

Question 16

What is the drug target + site of action for thiazide or TLD?

Answer 16

→ Na+ and CL- co-transporters

→ in the early DCT

Question 17

What are the main side effects of thiazide or TLD?

Answer 17

→ Hypokalemia
→ Hyponatremia
→ Metabolic alkalosis (increased hydrogen ion excretion)
→ Hypercalcemia
→ Hyperglycemia (hyperpolarised pancreatic beta cells).
→ Hyperuricemia

Question 18

What happens after 1-2 weeks of using thiazides or TLDs?

Answer 18

lose their diuretic effects

Question 19

How do thiazides or TLDs maintain their anti-hypertensive effects after 1-2 weeks?

Answer 19

due to their vasodilating properties, especially for thiazide-like diuretics

Question 20

List 3 examples of angiotensin receptor blockers.

Answer 20

→ Losartan
→ Irbesartan
→ Candesartan

Question 21

What is the mechanism of action for angiotensin receptor blockers?

Answer 21

These agents act as insurmountable (i.e. non-competitive) antagonists at AT1 receptor (found on kidneys and on the vasculature)

Question 22

What are the drug targets of ARBs?

Answer 22

synaptic vesicle protein SV2A

Question 23

What are the main side effects of ARBs?

Answer 23

→ Hypotension
→ Hyperkalaemia (care with K+ supplements or K+-sparing diuretics)
→ Foetal Injury (AVOID IN PREGNANT WOMEN)
→ Renal failure (in patients with renal artery stenosis)

Question 24

What’s more effective? ARBs or ACE inhibitors?

Answer 24

ACE inhibitors

Question 25

Which ARBs are pro-drugs?

Answer 25

→ Losartan

→ Candesartan