He was due to appear at the High Court in Edinburgh today to appeal against the length of his sentence for the murder of schoolgirl Vicky Hamilton.
In February 1991, the 15-year-old disappeared while waiting for a bus near Tobin's then-home in Bathgate, West Lothian. Her body was found along with another of Tobin's victims, Dinah McNicol, in the garden of another of his former homes in Margate, Kent, in November 2008.
Tobin is being held at HMP Frankland in Brasside, Durham.
The Scottish Court Service confirmed the hearing had been withdrawn after Tobin had "taken ill".
A Prison Service spokesman said: "We can confirm that a prisoner at HMP Frankland spent a number of days in hospital. He has now returned to the prison."
Tobin, 63, was convicted of murdering Miss Hamilton at the High Court in Dundee in December 2008. A judge imposed a life sentence with a minimum recommendation of 30 years.
The handyman was convicted of murdering 18-year-old Miss McNicol last December while in prison for the murders of Miss Hamilton and a third woman, Angelika Kluk, 23.