The number of children who received hospital treatment for allergies has increased by 65% across England in the past five years, figures have revealed.
In 2013-14, 2,873 teenagers sought treatment whereas in 2017-18 it was 4,743, data from NHS Digital shows.
Allergy UK said this could be because this was the age when sufferers started taking responsibility for themselves.
There have been calls for the government to introduce legislation on how schools should manage allergies.
The figures from NHS Digital, released to BBC London under the Freedom of Information Act, also showed the number of children treated for anaphylactic shock increased by 41% in the past five years.
For teenagers, the increase was 36% while for those aged 19 and over, it increased by 10%.
Amena Warner, head of clinical services for Allergy UK, said one reason why more teenagers were receiving treatment was because at that age, allergy sufferers started to move away from parental control.
She said teenagers might not question food the same way as parents did and may not read food labels in detail, while sufferers might also be more inclined to seek hospital treatment because they had more awareness about what happened during a reaction.
Dr Paul Turner, a consultant in Paediatric Allergy and Immunology at Imperial College London, said risk-taking or a lack of self-confidence in managing food allergies was “almost certainly a factor in the increase in non-fatal anaphylaxis in this age group”.
Food allergies affect about 7% of children in the UK, according to Kings College London.
Schoolboy Karanbir Cheema died in 2017 after he had a severe reaction to cheese that was thrown at him while he was at school.
Following an inquest, the coroner said it was “vital” allergy action plans were standardised in hospitals and schools.
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However, allergy specialist Prof Adam Fox said he was seeing a lot of occasions when schools seemed to be failing families.
“In the most extreme cases, parents seem to be genuinely frightened to send them to a school where they don’t feel safe,” said Prof Fox, a paediatric allergist at Evelina London children’s hospital.
A parent’s view: ‘They don’t get it’
Jenna Laing-Phillips, whose 10-year-old son Stanley has severe allergies, said it could be “overwhelming because you spend every day thinking about minimising risks”.
“Food is the easy bit in a way, but then you do have to think about the surfaces he’s touching, the handles he might be touching. These are the issues we had at school, they don’t get it… the risk of cross contamination is huge.”
She took Stanley out of his old school in Surrey, saying she believed it did not have proper safeguards in place to protect him, but the school denied the claim and said safeguarding was its “top priority”.
It also said there were no recorded incidents of an allergic reaction by Stanley while he was in the care of the school.
“What we want to know is that our kids are safe in school and that they’ve done everything they can to minimise the risk and if something was to happen, the school will know what to do because actually they have clear legislation to follow,” Ms Laing-Phillips said.
She launched a petition calling for the introduction of statutory allergy legislation.
In its response, the government said it considered the “existing legislation combined with statutory guidance to be sufficient”.
All primary and secondary schools in the UK are able to buy adrenaline auto-injectors without a prescription for use in emergencies but some have called for more guidance from the government.
At Crowthorne Church of England Primary School in Berkshire, lunch boxes are checked by staff while photos and care plans have been put in place for every child with a food allergy. Every member of staff has also been trained to use an EpiPen.
But head teacher Ruth Jackson said better guidance from the government would be reassuring.
“It would be good for head teachers to know what good practice is and to make sure that they are following it because ultimately what every head teacher wants is to make sure they’re doing the best for every child,” she said.
The Department for Education said it was “clear that children with medical conditions should be properly supported to enjoy a full education and be safe at school”.
“All schools are required to make arrangements that ensure this is the case,” a spokesperson said.