Smash Mouth's lead singer was rushed to the hospital via Uber.
Steve Harwell, 50, called for a car to rush him to the emergency room Thursday night after he was having trouble breathing during sound check ahead of their Memphis, Tenn. show, TMZ reports.
Harwell was suffering from the effects of the condition cardiomyopathy, which he's had for two years, according to the gossip site.
The "All Star" singer had reportedly had not been feeling well for the past four days, but never to the point couldn't he perform.
He told the tour manager during sound check that he wouldn't be able to take the stage that night, leading the band abruptly canceled the concert.
"Due to an emergency illness with a member of the band, tonight's show is now cancelled," a message by the New Daisy Theatre stated on Facebook.
"We are immediately working on a reschedule date. All currently purchased tickets will apply to the new date. If you would like a refund, please reach out to your point of purchase."
Harwell was given oxygen, IVs, steroids and inhalers, according to TMZ.
Cardiomyopathy is a disease of the heart muscle making it difficult for the organ to deliver blood to the body. At its worst, it can lead to heart failure.
Symptoms include shortness of breath, leg swelling and bloated stomach.
THEN AND NOW: '90s and '00s boy bands
O-Town THEN: The boys in 2002. How long did that hair take?
O-Town NOW: Pictured in April 2017, the men are back in action with a new single! They lost one member (and the spiky hair), but a major comeback is on its way.
BBMak THEN: The "Back Here" trio were all the rage in the early '00s.
BBMak NOW: The band broke up in 2003. Christian Burns (pictured) still pursues music.
BBMak NOW: And Mark Barry is a personal trainer!
LFO THEN: They're best known for "Summer Girls," which had goofy lines like "New Kids On The Block had a bunch of hits / Chinese food makes me sick."
LFO NOW: Unfortunately, a member of the trio, Rich Cronin, passed away in 2007 after a battle with leukemia.
LFO NOW: The remaining members of LFO, Devin Lima and Brad Fischetti, are still tight -- and making music!
Dream Street THEN: The pint-sized performers hit it big in the early 2000s, but their demise came quickly: Parents of the boys reportedly sparred over their contracts.
Dream Street NOW: Now 30, Jesse McCartney is a major ex-boy band success story! He branched out on his own and has thrived as a solo star. He's pictured here with girlfriend Katie Peterson.
Dream Street NOW: Other ex-members of the band include Greg Raposo, who continues to pursue music...
Dream Street NOW: ...and Chris Trousdale, who's taken up a modeling career.
Hanson THEN: Back in 2000, the mop-headed brothers were as known for their hair as they were for catchy songs like "MMMBop."
Hanson NOW: They're all grown up! The trio continues to release new music and has an ultra-devoted fan base.
All-4-One THEN: The foursome's romantic ballad "I Swear" is still a favorite for wedding first dances.
All-4-One NOW: The men are all grown up! Here they are in March 2017.
The Backstreet Boys were lookin' fly in 2000 as they debuted "Millennium," which included some of their all-time biggest hits.
Nearly two decades after their heyday, BSB is still in action -- and fans are obsessed! They perform in Las Vegas to huge audiences and have continued to tour across the country.