Amy Winehouse's Grammy performance last week was a big step for her in that it was the first set that anyone could understand in recent memory.

The troubled singer appears to be finally on the road to recovery... and her husband being safely behind bars might be playing a large role in that.

Blake Fielder-Civil - locked up in London's Pentonville prison on assault and witness tampering charges - was rushed to the jail's hospital block when he collapsed in agony after taking what he believed to be heroin.

Guards found him "writhing in agony whilst being violently sick in a cell. They set off alarms and activated emergency procedures to save his life."

After an investigation, officials found Blake Fielder-Civil had taken a drug believed to be heroin, mixed with another toxic substance.

A jail insider said: "This was a close call, but he might not be so lucky next time. If he carries on taking so many drugs, he'll end up dead."

Cops believe Blake Fielder-Civil and six other prisoners took the drug in the G Wing of the north London prison. Within moments they had all fallen ill.

Amy Winehouse's husband of about a year has been warned to quit drugs. Just days before the OD, Blake Fielder-Civil was hauled in front of prison bosses for failing three random drug tests. He was locked in solitary as a punishment.

The jail source added: "He's being very stupid. It's only because everyone reacted so quickly that this dodgy gear didn't do long-term harm."

A Prison Service spokesman said only: "A small number of prisoners were treated in health care following the consumption of an unknown substance."