Unfortunately there is no set answer to this question, however what I do know is that a career in medicine is a life-long commitment and vocation so before you enter into that world you want to be pretty certain you're making the right choice! Work experience is suppose to get you exactly what it says...experience in the field of work that you're interested in. You don't want to pursue a career as a doctor then faint the first time you try to take blood. All I can recommend is to try and get experience in a variety of sectors - GP, hospitals, charities and to shadow a variety of people - medicine is all about working in a multidisciplinary team after all. It doesn't matter about the amount of experience you can get but how much you can get out of it, so keep your eyes open for reasons why being there proves to yourself that a career in medicine is something you must pursue.