Perry collapsed in his dressing room after performing Walk This Way on stage. The 68-year-old Perry had recently announced a new single and solo tour. Aerosmith has also planned a Las Vegas residency for next year.
Perry was taken out of the Garden on a stretcher after paramedics worked on him in his dressing room, reportedly inserting a tracheal tube down his throat at one point.
No updates on his condition have been reported.
Perry has contributed to numerous soundtracks and has occasionally appeared as an actor in minor roles.
This recent lapse follows a 2016 incident in which Perry also collapsed backstage before a performance by the Hollywood Vampires, a band featuring Johnny Depp and Alice Cooper. EMTs on site revived Perry and immediately transported him to the hospital in that incident.
Perry has a well-documented past with drug and alcohol problems, issues which at one time derailed Aerosmith. But he recovered and resumed a busy career with the band and solo work.