Facebook.com/DavidCassidyA spokesperson for Partridge Family star David Cassidy is blaming cold medicine for the singer's apparent meltdown Sunday during a Las Vegas concert that was a tribute to late Monkees singer Davy Jones.

Cassidy's rep tells the Las Vegas Review-Journal that a combination of cold medication and medicine for a skin condition led to the singer's reportedly shambolic performance at the South Point Hotel and Casino last Sunday.  During the show, more than 50 disgruntled patrons walked out.

"He was so out of it from the combination [of the two medications] that he thought he would pass out and, the next day, didn't even know there had been a problem until he was told," the rep said.

Earlier in the week the paper quoted one show attendee as claiming that Cassidy rambled throughout the show, apparently unaware that he was repeating himself, and berated the audience, telling them to shut up and just clap.

Cassidy's rep tells the paper that the former teen idol, now 62, plans to pen an apology for his website and "feels awful about any embarrassment he caused the venue, his band, fans and other audience members."  The rep added that Cassidy is now "offering to perform a free show at South Point to benefit a charity of their choice."

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