If what sources say is true, Steven Tyler was right about Aerosmith bandmate Joe Perry's need to slow down. Friends of the guitarist have apparently said overwork caused his collapse backstage during a July 10 performance by the Hollywood Vampires in Brooklyn.

Perry was subsequently hospitalized, as rumors of cardiac arrest spread. He was later reported to be in stable condition, but Perry's ailment was never explained. Now sources have apparently confirmed to the Premiere Radio Network (via Blabbermouth) that "a combination of dehydration and exhaustion" is to blame.

Perry was seen at Coney Island Hospital before being transferred to Manhattan's Columbia Presbyterian and then released. He's reportedly resting now at home in California. The Hollywood Vampires tour has since continued without him.

Tyler, who co-founded Aerosmith with Perry in 1970, made a similar diagnosis for his longtime bandmate. "I think he's out there and someone's overbooking him," the singer said last week. "They're doing like eight or nine shows in a row, or five in a row. I think they're all a little burnt. I think they may need to look at that. Not young anymore, you know?"

Perry started working with the Hollywood Vampires, which also features Alice Cooper and actor Johnny Depp, during Aerosmith's hiatus last year. Tyler, meanwhile, just released a country-themed solo album. The Vampires also feature Matt Sorum of Guns N’ Roses and Velvet Revolver, and Robert DeLeo of Stone Temple Pilots. Perry is expected to rejoin the tour.

Exclusive Photos of the Hollywood Vampires Performing in Brooklyn

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