A MUM is demanding an apology after she suffered an allergic reaction in Costco.

Mum-of-one Leah Clayton, 24, was shopping with her fiancé, nan and baby when she suffered a reaction to an orange-flavour Nakd bar in the Southampton store.

The bar was already cut up and not in packaging when it was given to her as a taster from a stall in the store. Leah said a server told her the bar did not contain nuts.

But Leah - who is allergic to nuts - quickly started to feel her tongue and throat tingle and was sick in the store.

She went to see a GP who said it was lucky she did not eat more of the product.

Daily Echo: Costco, Southampton.Costco, Southampton. (Image: Costco)

She is demanding an apology from Warehouse Demo Services, which provided the staff at the stall.

She told the Echo: “The members of staff in Costco that dealt with me being sick were lovely. I can’t fault them.

“It was just the man that was serving it that assured me there were no nuts in it.

“I just want to make other people aware because they’re not accepting any liability for it.

“They’re being, to be honest, quite rude about it.”

Leah, who lives in Eastleigh, first became aware of her nut allergy around two years ago and claims she asked the server twice if the bars contained any nuts.

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She was told that only one of the products contained nuts, but the orange one she was trying was nut-free.

Leah complained to Warehouse Demo Services and it opened but then closed an investigation into the incident.

She said: “They said 'we’re closing the investigation because we feel like all our policies and procedures were followed'.

“Their words were that it was an unfortunate occurrence.

“I’m not saying I was expecting a massive sort of payout or anything but just something to show their apology."

Dave Curtis, CEO of Fizz, the company behind Warehouse Demo Services said: “We are dealing with the member's complaint and if required, will contact the member directly regarding this matter.”

In an email, seen by the Echo, the company said an allergy sign was on display, the product packaging said the product contained nuts, and that an "experienced, trained" demonstrator informed everyone that it contained nuts.