Ozzy Osbourne has been admitted to hospital after suffering from flu, wife Sharon said.
The heavy metal star, 70, experienced “complications” from the illness, she said, and doctors advised him to go to hospital.
Sharon, 66, tweeted: “As some of you may have heard, Ozzy was admitted to hospital following some complications from the flu.
“His doctors feel this is the best way to get him on a quicker road to recovery. Thanks to everyone for their concern and love.”
Former Black Sabbath vocalist Osbourne, a Rock And Roll Hall Of Fame inductee, was forced to postpone the UK and European legs of his No More Tours 2 tour after taking advice from doctors.
He had been suffering from flu and was diagnosed with a severe upper-respiratory infection, according to a January 29 statement on his website.
Doctors feared the infection could develop into pneumonia had he toured, the statement added.
Osbourne, also known as The Prince of Darkness, is the former lead vocalist of heavy metal band Black Sabbath, the group he formed in 1969 alongside guitarist Tony Iommi, bassist Geezer Butler and drummer Bill Ward.
The group are widely credited with inventing and popularising the heavy mental genre of music.
As a solo artist Osbourne has released 11 albums with his debut Blizzard Of Ozz arriving in 1980.
It featured two of his most revered songs, Crazy Train and Mr Crowley.
Birmingham-born Osbourne has sold over 100 million records worldwide with Black Sabbath and as a solo artist.
He married Sharon in 1982 and they have three children together, Aimee, Jack and Kelly.
The family featured in their own reality TV show, The Osbournes, which first aired in 2002.