According to a report in today's Sun newspaper, the 34-year-old star was taken to hospital in Guildford after staff at the health spa where she is staying after pulling out of a West End show with stress dialled 999.
The newspaper said that shocked staff at Champneys Health Spa rushed to the aid of the Cilla star who is recovering after pulling out of London show Funny Girl a few weeks ago.
According to the report, two ambulances were called and paramedics attended before the actress was taken to the Royal Surrey County Hospital in Guildford.
She was later released and was said to have made a full recovery.
The health scare comes after weeks of openly sharing her problems with fans on Twitter.
The incident is understood to have taken place at around 5.20pm on Sunday.
Sheridan, who hails from the Isle of Axholme and who began her career in theatre in Doncaster, pulled out of the show at The Savoy Theatre, announcing that she would be taking two to four weeks off dues to "stress and exhaustion."
She has previously revealed on Twitter that her dad Colin is battling cancer.