CPRS 31: Calcium Antagonists

Question 1

Calcium blockers target which type of Calcium channels?

Answer 1

L-type

Question 2

Name 2 types of Vascular Selective Calcium Channel blocker. They focus on increasing vascular dilatation

Name 2 types of Cardiac Selective Calcium Channel Blocker. They focus on reduce the heart rate, reducing SA and AV conduction.

Answer 2

Name 2 types of Vascular Selective Calcium Channel blocker:

• Nifedipine
• Amlodipine

Name 2 types of Cardiac Selective Calcium Channel Blocker

• Verapamil
• Diltiazem

Question 3

What are some special stuff about Vascular Selective Calcium channel blockers?

• What is special about nifedipine compared to amlodipine? Consider in terms of heart rate and half life
• What are the adverse effects? Name 2-3

Answer 3

What are some special stuff about Vascular Selective Calcium channel blockers?
- What is special about nifedipine compared to amlodipine? Consider in terms of heart rate and half life
Heart rate: Nifedipine reduces the heart rate, amlodipine does not
Half-life: Amlodipine has a longer half life than nifedipine

• What are the adverse effects? Name 2
  Natriuresis
  Vasodilatation, cause reflex tachycardia
  Oedema

Question 4

What are some special stuff about Cardiac Selective Calcium Channel blockers?

• Will they cause vasodilatation
• Adverse effect? Name 1
• Need to be careful when administering the drug to patients with ___ dysfunction
• It is effective for arrhythmia due to ______ by reducing the calcium overload

Answer 4

What are some special stuff about Cardiac Selective Calcium Channel blockers?

• Will they cause vasodilatation: Yes; Slight Vasodilatation
• Adverse effect? Heart failure
• Need to be careful when administering the drug to patients with hepatic dysfunction
• It is effective for arrhythmia due to delayed after depolarization by reducing the calcium overload

Question 5

Name 2 alpha receptor blockers

What are their limitations

Name 1 adverse effect

Answer 5

Prazosin
Doxazosin

Limitation: Inhibit Alpha receptors will lead to decrease in BP, leading to increased renin release, which will lead to blood pressure increase eventually

Adverse effect: First dose phenomenon (e.g. orthostatic hypotension)

Question 6

Name 3 types of beta receptor blockers

Answer 6

Propranolol
Metoprolol
Pindolol

Question 7

Pindolol is a _____ agonist for beta receptor, but are antagonists for ________ (which stimulates beta receptors)

Answer 7

Pindolol is a partial agonist for beta receptor, but are antagonists for catacholamines (which stimulates beta receptors)

Question 8

Name some adverse effects of beta receptor blockers

• Respiratory tract
• Liver
• Heart
• Smooth muscle

Answer 8

Name some adverse effects of beta receptor blockers

• Respiratory tract: Bronchospasm
• Liver: Hypoglycemia (Constricted duct, less glucose comes out)
• Heart: Increase heart failure and arrhythmia chance
• Smooth muscle: Vasoconstriction