The Daily Record reported that Tobin was taken to the Royal Infirmary of Edinburgh from Saughton prison after he became unwell on Thursday around 7:30pm.
It is understood the 74-year-old murderer is suffering from cancer and this is not the first time he has visited hospital, with sources claiming that he is well known for feigning illness.
In 2016 he was found “slumped” in his cell. Four years earlier he landed in hospital suffering stroke-like symptoms, though medical staff found no evidence of an issue.
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The Sun reported that insiders told of how Tobin was in a “bad way” when he was rushed to hospital this time.
A jail source said: "The guards immediately rushed to help him and they were all shouting ‘code blue, code blue’.
"He was rushed to hospital and the whole wing was locked down for a while after.
"All the guys in here hate him – he's evil.
"We all hope he really has had a stroke.
"The sooner he is gone for good, the better."
In 2008 the now 75-year-old was jailed for murdering Vicky Hamilton in 1991.
Ms Hamilton, 15, was killed in Bathgate on her way home to Redding, Falkirk. Afterwards Tobin dumped her bag in Edinburgh.
He is also serving a life sentence for the murder of Dinah McNicol from Tillingham, Essex, who was just 18-years-old.
The bodies of both victims were found in Margate, Kent, in the garden of a house that Tobin moved to from Bathgate.
Tobin also raped and killed a 23-year-old Polish student, Angelika Kluk, whose body was found in a storage area under a church in Anderston, Glasgow.
In addition to killing Ms Kluk, Ms McNicol and Ms Hamilton, police believe he may be responsible for a number of other unsolved murders.
Tobin’s trial in 2009 for murdering Ms McNicol was interrupted three times after he complained of having chest pains and shingles, leading to him being taken out of Chelmsford Crown Court.
A spokesman for the Scottish Prison Service said: “We cannot comment on individual prisoners.”