Bret Michaels cancels charity gig over flu

Bret Michaels has cancelled an appearance at the XSport Fitness Rock 'n' Roll Chicago Half Marathon due to illness.

The Poison frontman was scheduled to perform at the end of the race, but was forced to pull out early today after experiencing "severe dehydration".

"We are sorry to announce that Bret Michaels was not able to take the stage this morning due to a sudden bout of severe dehydration and the flu," read a statement from marathon organisers.

It continued: "The entire Rock 'n' Roll Marathon Series family wishes Bret a quick and healthy recovery and we look forward to his participation at our upcoming events."

Michaels later tweeted fans his apologies, telling them that he regretted the cancellation.

"Not only feeling bad physically, but also feeling bummed about missing the show today in Chicago," Michaels wrote. "Such great fans!…"

In May, Michaels described his 5-year-old daughter Jorja as his karmic "payback", admitting that the child reminds him of himself as a kid.

The 48-year-old experienced a number of health problems last year, including suffering a brain haemorrhage in April. He has since said that he is lucky to be alive.