How would you approach a patient claiming to have a reaction to a medicine he/she has been on all his/her life, with the additional aspect being it is a reaction that isn’t typical of an allergy?

This question may be asked to see what your threshold is for ignoring a patient's complaints. The interviewer wants to know not only your sensitivity to respecting what is reported, but also where you draw the line. Drawing it too conservatively may put the patient in danger, and drawing it too liberally may result in unnecessary and costly diagnostics and/or treatment.