The drummer from Aussie band 5 Seconds of Summer told fans he'd suffered 'symptoms of a stroke' while performing in the US.
Ashton Irwin, 27, was live on stage with bandmates Luke Hemmings, Michael Clifford and Calum Hood in Texas when he began feeling unwell.
Taking to Twitter, he explained: “I suffered from an intense migraine brought on by exhaustion and overheating onstage which made me loose (sic) my vision and gave me symptoms of stroke in the left side of my body. So the decision was to end the show there and then.”
The drummer was immediately taken to hospital, admitting the whole experience was 'overwhelming'.
"I was in tears in the ambulance, because I feel I’ve let many people down. I’m looking after myself and getting rest now," he said.
“I feel so loved and looked after by my brothers and team and all of you.
"This is the price a dehydrated drummer pays when he takes on Texas heat. All will be made right, ticketing wise, and rescheduling wise. I love you. Thanks for the love. I’ll be back onstage ASAP! X”
Luckily, fans of the Long Way Home stars won't have to wait too long as the band will be back to business next month.
Sharing an update on Instagram, they wrote: “Following medical advice, we will be postponing our show in Arkansas tomorrow night. The new date will be July 26th so Rogers, AR, will officially be our last show of the North American TMH tour!
“We are so sorry to cause inconvenience to your plans, but we promise for those of you who can still make it, we will put on the show of your lives.
“In the meantime, please join us in giving Ash the privacy to rest up and get back to full fitness.”
The Sydney-based band formed in 2011 and started out their career as YouTube celebrities.
They rose to International fame after performing with One Direction on their Take Me Home tour.
Since then they've gone on to sell more than 10million albums and two million concert tickets worldwide.