Actress Lindsay Lohan confirmed on her Twitter page today that she failed a court-ordered drug and alcohol test.
The star of 'Mean Girls' said that if asked, she is ready to appear before the judge in her case and face the consequences for her actions.
In a series of messages posted late last night, Lohan said: "Regrettably, I did in fact fail my most recent drug test."
She also said: "Substance abuse is a disease, which unfortunately doesn't go away overnight. I am working hard to overcome it."
Lohan often posts updates with the account that is verified by Twitter as belonging to the actress.
A source familiar with the case confirmed the positive test results for The Associated Press earlier on Friday.
The person declined to specify what substance triggered the positive result, which the source said occurred within the last month.
The failed drug test was first reported by TMZ.com.
The test result could mean a probation violation and more jail time for the 24-year-old actress. In July, Lohan was sentenced to three months in jail followed by three months in rehab after violating probation stemming from a pair of drug and driving under the influence cases filed after two arrests in 2007.
She ended up serving two weeks in jail and another 23 days in an inpatient rehab treatment at the Ronald Reagan UCLA Medical Center.
At a hearing last month, Los Angeles Superior Court Judge Elden S Fox ordered the actress to attend psychotherapy, drug and alcohol counselling as well as random drug and alcohol testing several times a week.
Compliance would allow her to return to unsupervised probation in November.
The judge had threatened Lohan with 30 days in jail for each probation violation.
A hearing would be conducted before Lohan could be returned to jail. Los Angeles County District Attorney spokeswoman Sandi Gibbons said no such hearing had been scheduled as of Friday afternoon.