The British star was treated for a 'serious respiratory infection', according to TMZ. The website reports Elton was cared for at Cedars-Sinai Medical Center in Los Angeles. He reportedly checked in at 6am on Wednesday morning and underwent several tests.
The star has been completing his Greatest Hits Tour since last year but has been told he needs to have 'complete rest and antibiotic treatment to prevent damage' for at least a week, according to the site.
It means he has called off four shows he was due to give in Las Vegas over the weekend.
'It feels strange not to be able to perform these Million Dollar Piano concerts at the Colosseum... I love performing the show and I will be thrilled when we return to the Colosseum in October to complete the 11 concerts,' he said. 'All I can say to the fans is, 'Sorry I can't be with you.''
The site reports the 65-year-old star has now been released from the medical centre.