Singer and reality television regular Peter Andre has been taken to hospital "in excruciating pain", a spokeswoman for the star said.
The former chart star was due to play at the Plymouth Pavilions on Friday night, but the concert has been postponed.
Andre's manager Claire Powell said: "We are very worried about Peter and at present we do not know what is causing him to be in so much pain. Peter is terribly disappointed that he is unable to perform at tonight's sold-out opening night.
"At this time we have no more information though we are hoping Peter will be able to perform at Minehead tomorrow as planned. We will keep his fans informed via his website www.peterandre.com for further information on the situation."
The Plymouth concert has been re-scheduled for Tuesday December 21.
Andre is best known for his marriage to glamour girl Katie Price which ended in September last year. The pair married after romance blossomed in front of viewers on I'm A Celebrity...Get Me Out Of Here!
They have two children together, Junior, four, and Princess Tiaamii, two, alongside Price's son Harvey with footballer Dwight Yorke.