More accidents involving loom bands are being reported around the country.
A child in Bristol nearly lost his finger after falling asleep with one of the bands wrapped round his finger.
Now seven-year-old Kyle Lawrence from Cleethorpes in Lincolnshire has been temporarily blinded after his brother accidentally pinged a bangle into his eye, causing a blood clot.
He was rushed to hospital and admitted for six days. He has still not regained the sight in his left eye.
Loom bands are brightly-coloured rubber rings than can be weaved together to make bracelets and are the latest craze among young children.
Children also stretch them to play games and make bracelets.
A doctor from Bristol has issued a warning to parents over safety fears about the bands after the boy in Bristol nearly lost his finger.
The doctor, a mother of three, said on a mother's Facebook group: "Please be careful with looms - zoom in on the fingers - the parent of this child thankfully went in to check on him half an hour after lights out."
Sales of loom bands rocketed after the The Duchess of Cambridge was spotted wearing one of the multi-coloured bracelets during a royal tour of New Zealand.
Her parents Carole and Michael Middleton now sell a similar product through their mail order company Party Pieces.
David Beckham and One ~Direction's Harry Styles also wear them which has made them extra popular with children.