The 40-year-old pop star opened her Lifetimes Tour at the Qudos Bank Arena in Sydney on Wednesday night and admitted to her audience she had been struggling with jet lag, particularly because her and Orlando Bloom's four-year-old daughter Daisy had been waking her up at 5am, but joked any visible signs of tiredness weren't there because she'd had the wrinkle-smoothing injections.
"You can't tell I'm tired because I got fresh botox for Australia," she told the crowd.
Katy also made her audience laugh when she called for her assistant to come on stage and help her unzip her costume.
She explained she was struggling with the garment "because I've been eating too many Tim Tams".
During the Choose Your Own Adventure segment of the show, the Teenage Dream hitmaker - who will be performing another 14 shows Down Under this month - invited a group of young fans on stage to sing Thinking of You with her, including one boy in a shark costume, which referenced her infamous Left Shark dancer during her 2015 Super Bowl halftime show.
And that wasn't Katy's only interaction with her young fans, as at one point, she bent down from the stage to thank one supporter for "waiting for five hours" to secure a spot on the front row.
This isn't the first time Katy has confessed to having botox treatments.
Last month, a satirical headline by the Onion joked Katy would be releasing a song called Stop Making Fun of Me alongside a photo of Katy taken in Melbourne last year.
She quipped on Instagram in response: "This photo is clearly photoshopped I would never let my botox go that long, do better The Onion!" With AAP.
