Amy Winehouse leaves hospital

A spokeswoman for University College Hospital, where the Rehab star spent the night, said she was ushered out via a private exit shortly after 9.45am.

She was said to be in good spirits after a "comfortable night".

An ambulance was called to the 24-year-old's house in Camden, north London, on Monday evening after she suffered the reaction to medication, according to her spokesman, Chris Goodman.

Winehouse's father, Mitch, was believed to have spent the night at the singer's bedside. He entered the hospital at 11.50pm and asked reporters and photographers to leave the family alone.

However, when asked how his daughter's condition was, he held up a bag of KFC and replied: "This is how serious it is."

The singer has publicly battled health problems recently, with the imprisonment of her husband, Blake Fielder-Civil, causing obvious stress.

She was caught on video in January apparently smoking crack cocaine in footage obtained by the Sun newspaper.

She also spent a stint in rehab before well-received performances at the Grammys in February.

Then in June, sets at the Glastonbury festival and the Nelson Mandela 90th birthday concert were thrown into doubt when she collapsed at home and underwent tests.