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). 

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College Answer

Most candidates were able to classify the calcium channel blockers well (Type I : 
Phenylalkylamines eg verapamil, Type II : Dihydropyridines eg nimodipine and Type III : 
Benzothiazepines eg diltiazem) However, the comparison of the pharmacology of nimodipine and 
verapamil was in general answered poorly. Few candidates demonstrated an organised 
approach to this part of the question. The two drugs’ presentation, routes of administration, 
indications and dosing were poorly answered considering that nimodipine in particular is used 
frequently in intensive care units. Mode of action was well answered, but important principles 
relating to pharmacokinetics (such as a basic outline of protein binding, bioavailability, and 
metabolism) were expected, but common omissions. More knowledge than ‘metabolism in the 
liver’ is required. Few candidates mentioned interactions, adverse effects, or predictable effects 
of over dosage of these drugs