65% of candidates passed this question.

This was a standard compare and contrast question of common analgesic pharmacology and it was generally well answered. The use of a table ensured all areas were covered including class, indications, pharmaceutics, mode of action, pharmacodynamics, pharmacokinetics and adverse effects. The uncertain nature (and possibilities) of the mechanism of action of paracetamol was alluded to in better responses.

Details of the comparative pharmacokinetics were often lacking. Answers should have included a comment on first-pass effect, the significance of the difference in protein binding and the details of metabolism, particularly paracetamol. Metabolism limited to “hepatic metabolism and renal excretion” gained no marks as better responses were more detailed and clearer about the differences between the two drugs. Knowledge of metabolism at therapeutic doses and the effect of overdose were expected. Better answers included potential interactions with other drugs (e.g. warfarin) and contraindications to the use of these drugs.