Antihypertensives — Calcium Channel Blockers

Current · V5 (2025) → D7.iii Historical · V4 (2023) → G7.ii 4 exam appearances

2022B Q08

Exam question

Classify calcium channel blockers providing examples (15% marks). Describe the pharmacology of verapamil (85% marks).

CICMWrecks answer

Master answer

Class I – Phenylalkylamines:
- Verapamil
- Reduces HR, contractility and causes vasodilatation, decrease in cardiac contractility, heart rate, and both coronary and peripheral vascular tone.
Class II – Dihydropyridines:
- main effects are on vasodilatation
- 1st gen = nifedipine
- 2nd gen = felodipine, nimodipine
- 3rd gen = amlodipine
Class III – Benzothiazepines:
- diltiazem
- some reduction in HR and contractility, also causes vasodilatation, mild to moderate decrease in myocardial contraction, and decreases heart rate by decreasing both the automaticity of the SA node and the rate of conduction in the AV node.

Heart
- V-W Class 4 antiarrhythmic
- Decr SA node automaticity
- Decr AV node conductivity
- Vasodilation
- Negative inotropy
- reflex tachycardia
2) Vasculature
- Decr SVR and BP
- Decr Hypoxic pulmonary vasoconstriction
- Incr coronary and cerebral blood flow
3) Other
- Tocolytic
- NDMR potentiation.

Gladwin / JC 2021

Answer by Gladwin, JC

Past papers

4 appearances

Exam	Exact exam wording	Candidate success
2022B Q08	Classify calcium channel blockers providing examples (15% marks). Describe the pharmacology of verapamil (85% marks).	35%
2017B Q08	Classify calcium channel antagonists and give one example of each class (30% of marks). Describe the pharmacology of Nimodipine including important drug interactions (70% of marks).	19%
2014A Q02	Classify calcium channel blockers, and give an example for each classification. (30% of marks) Describe the pharmacology of verapamil. (70% of marks)	61%
2011B Q17	Classify the calcium channel blockers and provide one example of a drug for each class (20% marks). Compare and contrast the pharmacology of nimodipine and verapamil (80% marks).	36%