Lindsay Lohan Has Surgery

People reports:

Lindsay Lohan is having surgery to remove her appendix on Thursday.

"She does have appendicitis, and she is getting her appendix removed," her rep, Leslie Sloane, tells PEOPLE. "She will be going in shortly."

Lohan, 20, was reportedly diagnosed with appendicitis after feeling ill on Wednesday.

"I'm shocked," a friend of the actress tells PEOPLE. "I talked to her last night and she told me she was not feeling well but she thought it was a 24-hour-flu."

This is not the first health scare for Lohan. She fractured her wrist in September after a fall at a party in New York City, and was hospitalized in July after becoming "overheated and dehydrated," Sloane said at the time