A woman in a six-year vegetative state after taking a heroin overdose has made "fantastic steady progress" during a sleeping pill trial, her mother says.
Amy Pickard was severely brain-damaged by a heroin overdose
Amy Pickard, from East Sussex, is one of 300 people worldwide being treated with Zolpidem, an insomnia drug.
In 2006, researchers found that some patients in a vegetative state could be temporarily revived by taking it.
"Within 20 to 25 minutes [of taking the first pill] you could see the change in her face," said her mother, Thelma.
Ms Pickard, 23, experimented with heroin in 2001 and had to be resuscitated twice.
Her mother, from Sedlescombe, East Sussex, said she was not an addict, but she just "got in with the wrong people" through her boyfriend at the time.
Ms Pickard was still a teenager when she collapsed in public toilets in Hastings, and she was also seven months pregnant.
"We don't know exactly what happened, but she had 15 minutes of getting no oxygen to her brain and she suffered brain damage," her mother said.
"Unfortunately we also lost the baby."
A person in Ms Pickard's condition may appear to be awake and have their eyes open, but will show no awareness of their surroundings.
Thelma Pickard embarked on the Zolpidem trial after a visit to South Africa, which was filmed for a documentary called The Waking Pill being broadcast on BBC One on Wednesday.
She went with the programme makers to hear about South African patients given the pill who had then woken up "as if a switch had been flicked".
She said: "I'd actually heard about the pill about two years ago, but thought it wasn't within my grasp, and then it came to find me."
'Profound brain injury'
Her daughter is being cared for at the Raphael Medical Centre, in Hildenborough, Kent, which specialises in a holistic approach to rehabilitation.
And Mrs Pickard said the drug seemed to be having an impact on helping her come out of a state of limbo.
"It's all very, very exciting and my visits to Amy are far more exciting now," Mrs Pickard said.
"She is making fantastic steady progress... she moves so much better now.
"The main thing that you see straight away is with her eyes, she's much more aware and she will actually look around.
"She has a very profound brain injury... but Amy's team feel she's gaining from this pill so we're keeping her on it for as long as [possible]."
South African researchers writing in the NeuroRehabilitation journal in 2006 said three patients treated with Zolpidem had been temporarily revived from a permanent vegetative state.
Mrs Pickard and the BBC documentary team also travelled to the country with the parents of Joanne Douglas, from Prestwick, Ayrshire, Scotland, who has been unable to communicate since lapsing into a coma in 1995.