WHEN 11-year-old Calvin Lock came down with a suspected viral infection, his mother did not hesitate to give him ibuprofen.
The routine medication almost cost him his life after a violent allergic reaction left his body covered in severe blisters.
He had to be put on a life support machine and was treated in a specialist burns unit. All of his hair and fingernails fell out.
Calvin spent nearly three weeks in hospital during which his parents were warned he could die before being allowed home.
His mother Robyn Moult and stepfather Daryn Chambers are now campaigning to raise awareness of his condition, Stevens Johnson Syndrome, which is triggered by certain medications and affects three people per million each year.
Miss Moult, 38, who has three older children, said: "The doctors are 100 per cent sure that the ibuprofen caused Calvin's reaction.
"We would never have known that he was going to be allergic. I have given it to my other children and they have been fine.
"The severity of the allergic reaction was frightening. Literally every part of his body had blistered. Calvin looked like someone had poured petrol over him and set him alight.
"It was heartbreaking. I honestly thought I would not see Calvin again. He kept asking me if he was dying. He said he would see us on the other side. We got him to record goodbye messages to his brothers and sisters."
Calvin, a keen sportsman from Littleport, Cambridgeshire, had a sore throat on September 19 and his mother gave him a dose of strawberry-flavoured liquid Nurofen for children after his GP said he had a viral infection.
Six days later he returned to the GP with a rash and was diagnosed with chickenpox for which SJS is often mistaken and given antibiotics.
The next morning, swelling and rashes had appeared across his body and he was taken to Addenbrooke's Hospital in Cambridge.
Doctors there also diagnosed chickenpox and it was only 24 hours later when he was struggling to breathe and unable to walk, talk or see that he was admitted as an in-patient.
Calvin was put on a drip as staff started treated more than 200 painful blisters but his condition deteriorated and he was put on a life-support machine.
He was transferred to the burns unit at Broomfield Hospital in Chelmsford, where surgeons removed affected skin from 65 per cent of his body.
His mother added: ''Losing his hair has been tough and he hates the fact his skin looks so different. But his strength has been amazing. We're so proud of him.''