Mr Gascoigne was previously sectioned in February
The sister of former England footballer Paul Gascoigne has said she fears for his life after he was held under the Mental Health Act.
Anna Gascoigne told ITV News that her brother faced a "very dangerous" mix of depression and addiction.
Mr Gascoigne was released on Monday after being sectioned, but later voluntarily returned to hospital.
His former Tottenham team-mate Gary Mabbutt said the star was then sectioned again for up to six months.
Police confirmed that Mr Gascoigne was taken to hospital on Sunday after reports that he was acting strangely in Hemel Hempstead, Hertfordshire.
A police spokesman said Gascoigne had approached a member of the public and appeared to be unwell and in an agitated state.
He was released on Monday, but later that day police were called to a hairdresser in Kensington, west London, where he was "feeling unwell".
He then voluntarily presented himself to hospital staff.
Mr Mabbutt told the BBC that Mr Gascoigne was subsequently detained under section three of the Mental Health Act at the Priory hospital.
"Paul can be detained for up to six months, which means that even if Paul wanted to be discharged and wanted to leave tomorrow he is not able to leave," Mr Mabbutt added.
Anna Gascoigne told ITV News her brother had been given a lot of support by friends and well-wishers, but he needed professional help.
"He's been drinking, I believe, to escape, to get away, and it's been a vicious circle," she said.
"I have feared for his life, especially I would say the last couple of weeks.
"It had literally gotten to the point where I was having to be with him constantly, to the point where I was taking him to hospital because I believed that he needed help."
Football agent Eric Hall, a close friend of the player for nearly 20 years, described his condition as "far, far gone".
"I would like to think that there's a miracle cure, and somebody could sit down with Paul Gascoigne and say Paul, don't do this, don't do that, but do this and do that," Mr Hall said.
"I don't think he'll listen any more."
Mr Gascoigne was previously detained in February after an incident at a Tyneside hotel.
The ex-midfielder, who has battled with alcohol and health problems, was treated at Middleton St George Hospital in Darlington for two weeks following the incident.
In January 2005, Mr Gascoigne - nicknamed Gazza during his football career - was hospitalised with pneumonia and last year he underwent emergency surgery for a perforated stomach ulcer after being taken ill while he was celebrating his 40th birthday.
And in the same year he was arrested for an alleged assault on a photographer outside a Liverpool city centre hotel. The charges were later dropped.
A former player with Newcastle United, Tottenham Hotspur, Lazio, Glasgow Rangers and Middlesbrough, Mr Gascoigne was sacked after 39 days as manager of Kettering Town in 2005.
During his football career he was capped 57 times for England.