Michael told The Herald Sun, 'She suffered very serious attacks. She couldn't breathe and was doubled over in pain and had to be taken to hospital in an emergency ambulance.'
The Live Nation spokesman also said he understood the frustrations of disgruntled fans over the rescheduled shows.
'She's human, not a superhero taking a day off,' he said.
Yesterday, Pink took to Instagram to address fans personally.
She wrote, 'First, I want to say thank you to all of the kind people out there for your well wishes for my speedy recovery.
'On Monday, we were absolutely planning on going ahead with the show, and about 20 minutes before I left for soundcheck, I was rushed to the hospital, in excruciating pain. That was the reason for the late cancellation. It was out of anyone’s control, and of course, wasn’t planned that way.
'I was discharged from hospital last night, and am following doctors orders of liquids and rest.
'A lot of you know how physical my shows are, and that I don’t just stand in front a microphone and sing.
'I flip, dance, fly, harness, silk, and scream my way through a total shit show of awesomeness (no pun intended). Therefore, I need to be physically healthy and well in order to perform this show. I think all of you deserve the full show and me at my best.
'Our next show will be Saturday, and until then I will be drinking green tea, and spending time with my kids.
'That’s a warning to paparazzi, you might actually see me walking upright outside of my hotel room cage with two little children, and another warning: I might even smile. Not too much, though. I’ll try to control the smiling.'
Pink goes on to apologise
'My sincere apologies to any of the ticket holders that this has affected, the rescheduled dates will be announced today.
'Thank you for your patience, compassion, and support. I look forward to rocking out with all of you as we have done for many many years.
'All of my love. Pink
'I also want to thank the amazing doctors and nurses at St Vincent’s Hospital for taking such good care of me and getting me home to my kids.'
Pink's new shows will be:
Friday August 3 will now be on Friday August 24
Monday August 6 will now be on Monday September 17
Tuesday August 7 will now be on Tuesday September 18
Thursday August 9 will now be on Wednesday September 19
The Brisbane performance scheduled for Thursday, August 23 will now be on Wednesday, August 22 to allow for the rescheduled Sydney dates.
If you can't make the rescheduled date, Live Nation says: 'You can exchange your tickets for an earlier Sydney date whilst availability permits.'
Or, you can get a refund by visiting ticketek.com.au/contactus.