Kyle Busch cause of death revealed as severe pneumonia, sepsis as NASCAR star's family issue statement

NASCAR driver Kyle Busch died at the age of 41 after severe pneumonia developed into sepsis, his family have confirmed in a statement.

Busch, a two-time NASCAR Cup Series champion, was hospitalised on Thursday morning with what was described as a 'severe' illness.

On Thursday afternoon, his family, NASCAR and Richard Childress Racing - the team he drove for since 2023 - confirmed his passing in a joint statement.

"NASCAR lost a giant of the sport today, far too soon," the statement read in part.

"During this incredibly difficult time, we ask everyone to respect the family's privacy and continue to keep them in your thoughts and prayers. Further updates will be shared as appropriate."

Immediately after a NASCAR Cup Series race at Watkins Glen on May 10, Busch requested medical assistance through his team radio.

It was reported via FOX's live TV broadcast that he had a sinus cold.

READ MORE: Kyle Busch asked for doctor immediately after NASCAR race 11 days before death

Busch entered a Craftsman Truck Series race on May 15 - which he won - and told motorsport reporter Jeff Gluck the following day that he had been suffering from a 'substantial' cough.

"You can kinda still hear it. I'm still not great. But the cough was pretty substantial last week," he said.

He was due to take part in this weekend's Coca-Cola 600 - one of the sport's most prestigious races - at Charlotte Motor Speedway.

The Associated Press report that he 'became unresponsive' while testing in the Chevrolet racing simulator in Concord, Massachusetts on Wednesday before being transported to hospital.

Now, Busch's family have announced that they have received a medical evaluation following his death.

"The medical evaluation provided to the Busch family concluded that severe pneumonia progressed into sepsis, resulting in rapid and overwhelming associated complications," their statement reads, as per FOX reporter Bob Pockrass.

"The family asks for continued understanding and privacy during this difficult time."

NASCAR drivers pay tribute to Busch

The announcement of Busch's passing led to an outpouring of tributes from current and former NASCAR drivers that he raced alongside, including Dale Earnhardt Jr, Jeff Gordon, Denny Hamlin and his team-mate in 2026, Austin Dillon.

Earnhardt Jr said that he previously had a 'really challenging existence for many years' with Busch, adding that the pair 'luckily took the time to figure out our differences'.

"I was super eager for us to get on better terms," he wrote on Twitter. "But it was he who made the effort for that to be possible.

"We did some media together also to laugh through some of the things we put each other through many years ago.

"Most recently we had even been discussing him running my Late Model [a separate form of stock car racing] at Wilkesboro this summer.

"He seemed extremely happy and we had planned to meet up next Thursday to get his seat to the shop. He laughed over the idea of his fans and JRM fans having to cheer in unison during that race."

"Kyle was one of the greatest drivers in NASCAR history. No-one can deny that," Earnhardt Jr added. "But he was also a father, a husband, brother, son, and a friend to many.

"My heart is broken for the Busch family. I will never be able to make sense of this loss but I am thankful that we had found a way to become friends."

Dillon, the 2014 winner of the Daytona 500 and the grandson of team owner Richard Childress, penned a lengthy tribute to his RCR team-mate on Instagram.

"I grew up around some great drivers that came through RCR, including Hall of Fame drivers," he wrote.

"But during that time, there was one guy on another team, and we all knew that when he showed up, we were fighting for second place.

Kyle Busch and Austin Dillon were team-mates at Richard Childress Racing (Image: Getty)

"It was clear every race who had the most talent and who hated to lose the most. For obvious reasons, my family was never the biggest fan of this guy. He was the enemy at the time, and he was hard to beat.

"I could never really show my fandom, but secretly I was a fan.

"When you became available in 2023 it was a no brainer that we had to go after you. When I made the call, your response was hilarious. You asked, 'Do you think your grandpa would want me?'

"I had already checked with my grandpa, and his response was the same as yours. 'Do you think he would want to come to RCR?' I said, 'Yes. You are both the same people. You are RACERS'.

"I can't thank you enough, KB. You are the ultimate racer and my favourite team-mate and driver of all time. I always felt like I had your back and you had mine.

"I love you brother. Myself and all of the RCR employees will keep fighting and striving for more victories in your memory. Proverbs 3:5."