Demi Lovato

Demi Lovato's reps are knocking down reports that the 18-year-old Disney star is seeking help for drug or alcohol-related issues.

"Demi Lovato is not in treatment for drug or alcohol addiction. As we have said since she entered treatment last week, Demi decided to seek help for emotional and physical issues she has battled throughout her life," her reps, Tiffany Shipp and Jesse Derris, said in a statement. "She has taken this step in order to get her life in order."

Demi Lovato exits tour, enters treatment center

Life & Style reported Wednesday that the Sonny with a Chance star had been drinking heavily and doing cocaine before entering a treatment center on Nov. 1. Texas college student Brian Payne claims he saw Lovato do cocaine at a party in North Richland Hills, Texas, on Dec. 28, 2009.

Check out photos of Demi Lovato

Following the abrupt cancellation of her worldwide tour on Nov. 1, Lovato's reps announced she had left the tour to "to seek medical treatment for emotional and physical issues she has dealt with for some time."

After she entered the treatment center last week, a source close to her family told TVGuide.com that the singer has struggled with bullying, an eating disorder and cutting in the past. Another report from People attributed Lovato's decision to a physical altercation with one of her back-up dancers.