Two doctors, one in Texas and the other in California, are currently under investigation by federal DEA investigators, according to NY Daily News:
The doctors - one in California, one in Texas - are believed to have supplied the "Brokeback Mountain" star with the powerful painkillers Oxycontin and Vicodin, law enforcement sources said. Authorities want to know if the drugs were prescribed illegally.
"It's an ongoing investigation," a law enforcement source told The News Tuesday. "It's not clear if there was any wrongdoing."
Besides Oxycodone and Vicodin (also known as Hydrocodone), autopsy results also showed that Ledger's system contained Diazepam (commonly called Valium), as well as Temazepam, which treats anxiety or sleeplessness; Alprazolam (also known as Xanax); and Doxylamine, a sedating antihistamine often used as a sleeping aid.