09/06/2010 05:12 am ET Updated May 25, 2011

Lindsay Lohan's Intense Prescription Drug

According to sources familiar with Lindsay's most recent probation report, LiLo has a prescription for Dilaudid -- an extremely powerful painkiller ... often compared to morphine ... and even heroin.

As long as she has the prescription, Lohan is in the clear to pop the painkiller -- presuming she follows the dosage guidelines. We're told a doctor wrote the prescription after Lindsay's recent dental surgery. We do not know the quantity the doctor prescribed.

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