What is a Side-Effect?
A side-effect is any unwanted response to a medicine that produces symptoms (e.g. headache, vomiting) or illness (e.g. liver or kidney damage). The technical term used by doctors is an adverse drug reaction.

A side-effect is any unwanted response to a medicine that produces symptoms (e.g. headache, vomiting) or illness (e.g. liver or kidney damage). The technical term used by doctors is an adverse drug reaction.