Ketamine is increasingly popular as a recreational drug. So why are so many people taking it? And what can prolonged use do to your body? Reporter Hazel Martin travels to the north west of England to talk to users, those being treated in detox and rehab, and doctors who say they're now being inundated by young patients in need of help. The government is considering reclassifying it as a class A drug, so is that part of the answer? And if not, how else can the ketamine crisis be fixed?