Steven Tyler says that he is “really concerned and worried” that he hasn’t gotten any news from his AEROSMITH bandmate Joe Perry, who collapsed onstage and was hospitalized Sunday during a show with HOLLYWOOD VAMPIRES.

The AEROSMITH singer tells Billboard.com that he’s placed calls to check on the guitarist without any reply. “It’s starting to scare me a little bit,” Tyler says. “I know they’re putting out nothing, but he’s recovering, he’s really good, he fainted, exhaustion. But I know my brother. He’s just about the only other guy that’s as passionate about his art as I am. He’s always asking me to do three, four [AEROSMITH] shows in a row, and I can’t. I’ll blow my voice out. I know how to maintain my career, my health, and Joe’s passionate. I don’t think he knows how to. I think he’s out there and someone’s overbooking him. 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, y’know?