The 'Kismot' Restaurant organises an annual competition to consume its 'Kismot Curry' dish, but this year emergency services were called to the restaurant after two competitors became "very unwell" last week.
The Scottish Ambulance Service has urged the restaurant owner to consider reducing the hotness of the curry for the contest that draws several chilli aficionados but few manage to complete the challenge.
Participants sign a legal disclaimer before taking part in the competition, which raises money for the Scottish children's charity Chas.
Half of the 20 people who took part dropped out after witnessing the first 10 diners vomiting, collapsing, sweating and panting.
The contest was won by Beverly Jones, who managed to finish nine spoonfuls of the chilli-filled dish, while American student Curie Kim came second.
Both ended up in hospital, local papers here said.
Kim, 21, said: "This was for a good cause, but it came with a price. I have never endured such pain. It was very painful and felt like I was being chainsawed in the stomach with hot sauce on the chainsaw".
She added: "I have learned my lesson and will never do it again and, in fact, I will be cutting down on my spice intake full stop."
The woman, who won, ate the last bowl in four seconds and then ran outside. Contest organiser Abdul Ali said: "The British Red Cross we had on board could not cope. We put our hands up.
"We did have to call the emergency services for a couple of our participants."
A spokesman for the Scottish Ambulance Service said: "Two patients were taken to Edinburgh Royal Infirmary after becoming very unwell at Kismot restaurant.
"We would urge the organisers to review the way in which this event is managed in future in order to avoid another situation where emergency ambulances are required to treat their customers."
Local councillor Gordon Mackenzie called the event a "shambles", and said: "The owners owe a debt to the ambulance service, and I hope they'll find some way of making it up to them."