The family of an eight-year-old boy with narcolepsy are blaming the swine flu vaccine for his sleep disorder.Ben Foy suddenly falls asleep up to 20 times a day and often collapses without warning.His mother Lindsey, 33, and grandfather Brian Hamilton, 60, say he has also become bad tempered and blame his condition on the swine flu jab Pandemrix.The vaccine was given to almost a million children under the age of five in 2009 and 2010 before being withdrawn because of its links with narcolepsy.Ms Foy, a mother-of-three, said: ‘Before Ben had the jab he was a very healthy little boy. It was only after that he started showing symptoms of narcolepsy.‘It started gradually and at first he just seemed more tired than usual.‘He'd just started a new school year so we thought that might be causing it and didn't think much of it.‘Soon after, he started falling asleep and his teacher told us he kept napping at his desk and they would struggle to wake him up.‘He found it exhausting to walk home from school and he started collapsing so we knew it was something serious.’Mr Hamilton, a chauffeur, said: ‘Since Ben had the jab it has been an absolute nightmare for us.’Ben does not only have narcolepsy, he has also developed cataplexy - a sudden loss of strength triggered by a strong emotion such as excitement.He had the injection in January 2010 and started showing the first symptoms the following September.Doctors sent him for tests - including CT scans, sleep studies, MRI scans, blood tests, a lumbar puncture and an ECG - before he was diagnosed with narcolepsy two years later.Ms Foy, from York, said: ‘For two years doctors didn't seem to know what was wrong with Ben, which was very distressing for us.‘He would fall asleep up to twenty times a day and he started having mood swings.‘When he was younger we used to call him the little Peter Kay, he was very funny and happy. Now he has really changed and he can be bad tempered.‘It was only when I read about narcolepsy and its possible link to the swine flu jab that the penny dropped.‘As soon as we saw it we just knew that was it. It was like someone was describing Ben.‘The doctors had to carry out their tests before they could make an official diagnosis but it didn't come as a shock at all when they told us he had narcolepsy. We already knew it."Ben's family chose to treat his condition without the use of prescription drugs until May this year.Mr Hamilton explained: ‘The drugs initially offered to Ben are linked to anti-depressants and have very serious side effects.‘They are drugs you don't want a child taking if it can be avoided and so we went down the track of trying to alter and manage his lifestyle to combat the symptoms.‘We took him to a child psychiatrist and altered his diet. We also noticed that it was when Ben would get excited that he would collapse so we tried to manage that.‘The only thing he had to stop doing completely was playing football because he kept collapsing on the pitch.‘We were worried for his safety so he had to stop playing for around two years.‘Now he's older, he's able to recognize himself when he's going to collapse and he takes a few minutes out of the game so he has just started playing again.‘We have to keep a close eye on him when he's doing things like having a bath or crossing the road but we've managed his condition as a family really well and Ben takes it in his stride.