Ellis Burke's arm reacted to the tattoo as soon as he had it done while in Marbella, Spain.
When he went home to Oldham, Greater Manchester, a few days later, Ellis fell ill. He struggled to breathe, had a high temperature and started vomiting.
He was admitted to Manchester Royal Infirmary's burns unit after being diagnosed with severe toxic shock. Ellis's condition was stabilised after his wounds were cleaned and he is now on the mend.
Ellis's mum Shabana Murray has now warned against anyone having the black henna tattoo, which contains a chemical called para-phenylenediamine (PPD) and sometimes even kerosene or petrol.
She told her local paper: "As soon as he had it done it started to react so we washed his arm in the sea but it made no difference.
"The next day it started to blister so we went to the pharmacy and got some anti-allergy medication but it just got worse and worse.
"As soon as we got home we went to A&E where they just prescribed antibiotics and more Piriton but they didn't clean it they just put the dressing back on.
"A few days later he just suddenly went down hill and woke up struggling to breathe and vomiting, his temperature was 39.4C when the ambulance arrived.
"But it was only at the walk-in centre they finally diagnosed toxic shock and sent him to Manchester Royal where they said they've never seen such a bad reaction. In fact they said they were going to use his case to inform other doctors of the effects of PPD."
Shabana said she could never have imagined something so terrible and dangerous would have come from a temporary tattoo.
She said: "We've been going to the same resort for the last four years and my eldest son has had it done several times at the same place by the same guy."
In fact Ellis had one done the week before and was fine.
Shabana said: "People need to know about this and basically avoid having one because the consequences are serious and can be life-threatening.
"I knew nothing about this PPD until I came back and read about it online. As far as I know its use in henna tattoos is banned in this country.
"I now have to clean and dress his arm three times a day and it's likely there will be permanent scarring.
"He'll also be sensitive to anything with PPD in like hair dye so will have to be careful for the rest of his life."
More on Parentdish: Boy scarred by henna tattoo of Star Wars' Darth Maul
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