Question 8

Compare and contrast the mechanism of action, spectrum of activity and adverse effects of benzyl penicillin, metronidazole and clindamycin.

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College Answer

This question asked to compare and contrast, inviting candidates to tabulate their answers. 
Details concerning other elements of pharmacology (apart from mechanism, spectrum and 
adverse effects) were not required and did not attract marks. 
There was a lack of accurate detail in answers regarding clindamycin. Spectrum of activity 
mentioned by candidates was often quite narrow. The gram negative and anaerobic 
spectrum of activity afforded by benzyl penicillin was also not mentioned by many 
candidates. Adverse reactions were an opportunity to score marks - all drugs can cause 
nausea, vomiting, rash and hypersensitivity phenomena - especially the antibiotics. However 
it is important that specific side effects for each agent are also mentioned by candidates.
Information that related to the pharmaceutics, pharmacokinetic or pharmacodynamic 
properties of these drugs was not requested and did not score marks.