Sir Elton John suffered a "potentially deadly" bacterial infection during a tour, forcing him to spend two nights in intensive care and cancel concerts in the US, his management says.
The singer became violently ill at the end of a tour of South America last week, requiring him to return to the UK for urgent treatment.
Nine concerts that were due to be staged in Las Vegas and California over the next two weeks have been cancelled.
Sir Elton is now resting at home.
A statement by his management said infections of the kind suffered by the star were "rare and potentially deadly". It gave no details.
"Thankfully, Elton's medical team identified this quickly and treated it successfully. He is expected to make a full and complete recovery," it added.
Sir Elton is due to resume his schedule of live performances in the UK on 3 June.
"I am so fortunate to have the most incredible and loyal fans and apologise for disappointing them. I am extremely grateful to the medical team for their excellence in looking after me so well," the star said.
His Million Dollar Piano tour is due to end its run in May 2018.
The career of Sir Elton spans five decades and has been littered with accolades, hit singles and world records.
The 70-year-old singer has sold more than 200 million records, making him one of the most successful artists of all time.