Medical chiefs issued a warning today after two women who bought a health drink contaminated with a horse tranquilliser were left seriously ill in hospital.
The women, one aged 60 and the other in her 40s, suffered a severe reaction when they drank the aloe vera juice that they purchased at a school fair.
One of the victims collapsed into a 'vegetative state' according to her daughter and had to be revived by paramedics.
Both women, who have not been named, were said to be in a 'satisfactory' condition in the Leicester Royal Infirmary.
It has now been confirmed the drink was contaminated with Ketamine, an anaesthetic agent which slows the breathing. It is used by vets treating horses, but is also popular with recreational drug users.
Dr Philip Monk, a public health consultant with the Health Protection Agency, said: 'The Ketamine was probably neat.
'In the small doses such as these, it is unlikely to prove fatal but could cause serious damage.'
The women, who are suffering from respiratory problems, are believed to have bought it at the Abbey Mela in Leicester last Saturday, an Asian carnival put on by the city's Abbey Primary School.
The 60-year-old victim collapsed 'within seconds' of drinking a small amount of the juice and complaining of a burning sensation in her throat.
Her daughter said: 'It happened about 9.30pm last Wednesday. I received a panicked phone call from my father and arrived about five minutes later.
'When I got there, I thought she was going to die. My dad was crying as the paramedics were trying to revive her. It was awful.
'She was basically in a vegetative state. They thought she might have bleeding on the brain. I thought "that's it".'
Aloe vera juice is used for consumption and relief of digestive issues such as heartburn and irritable bowel syndrome.
Leicester City Councillor Rashmi Joshi, who is a friend of one of the woman, said: 'Her family are extremely worried about her.
'Her husband thought she had gone. But he worked on her until the paramedics arrived and they treated her for 20 minutes before she was taken to hospital.
Health officials have said that anyone who has recently bought the drink, made by Indian-based company Gayatri Herbals, should avoid consuming it and hand it over to police.
Dr Tim Davis, from the Leicester City Primary Care Trust, speaking on behalf of the Health Protection Agency, said: 'We are unaware how many bottles were sold. It was in a white plastic bottle, and is normally sold like a health product.'
A spokeswoman for Leicestershire Police said: 'We are working with the Health Protection Agency to look into how the drinks consumed came to be potentially contaminated.
'We are keeping an open mind as to the circumstances.'
Adrian Russell, the city council's director of environmental services, said he did not think the product was widely sold. However, one shop has already been completely cleared of it's stock.