An 11-year-old boy is recovering after an extreme reaction to Ibuprofen left him with 65% burns and on life support.
Calvin Lock was given Nurofen for Children by his mother for a sore throat on the doctor's advice. But a few days later clusters of spots started appearing all over his body.
The burns led to him losing 65% of his skin and the youngster had to be put on a life support machine.
He had blisters everywhere; all over his face, inside his mouth," said his mother Robyn Moult.
"He kept saying he couldn't swallow. When he opened his mouth and I looked inside I was absolutely horrified."
At first his GP, then A&E staff, had thought the spots were chickenpox and he was sent home from hospital. But in the early hours of September 28 Ms Moult was so worried she decided to take him back.
Eventually he was diagnosed with an extreme form of Stevens Johnson Syndrome - a life-threatening skin condition thought to have been triggered by the Ibuprofen.
Ms Moult said: "He asked me if he was dying and I said no and he kept saying I will see you on the other side.
"I said I will see you soon, you sleep well and I honestly thought I wouldn't see or hear him ever again. Not ever again."
The illness is notoriously hard to diagnose.
Dr Carol Cooper, a GP, told Sky News: "The initial symptoms are really quite vague.
"A reaction like this is unpredictable, it's also extremely rare and a very individual thing. It's right to remember that nothing comes free of any downside but I don't think you can blame anyone for what's happened."
In a statement, the makers of Nurofen for Children said it is saddened to hear about the case and are contacting with the family to establish the full details.
Dr Amoesh Bhatt, the firm's UK medical director, said: "Allergic skin reactions due to Ibuprofen and other painkillers for children are extremely rare.
"Children's Ibuprofen is a clinically proven treatment with a well-established safety record."
A month on, and the marks from the blisters are clear to see on every bit of Calvin's body. Five times a day cream has to be rubbed into his skin.
He said the loss of over half his skin is "a really big change that's going to be hard for me", adding: "Normally I can just go out in the summer just run about but now I have got to stay in the shade with lots of sunblock."
Calvin has been helped through the ordeal by a family in the United States whose 10-year-old is going through the same experience.
Now Ms Moult intends to fight to improve support and advice for others facing the same rare diagnosis.