Avenged Sevenfold drummer Jimmy "The Rev" Sullivan died on December 28, 2009 from an accidental overdose of prescription drugs and alcohol, Orange County Deputy Coroner Mitchell Sigal told Rolling Stone. Toxicology reports indicate that Sullivan suffered "acute polydrug intoxication due to combined effects of Oxycodone, Oxymorphone, Diazepam/Nordiazepam and ethanol."

Oxycodone is painkiller that substitutes for Codeine, Oxymorphone is a painkiller similar to Morphine, Diazepam/Nordiazepam are anxiety medications and ethanol is the intoxicant in alcohol. Actor Heath Ledger similarly died from acute polydrug intoxication on January 22, 2008. Sigal added that Sullivan also had cardiomegaly (an enlarged heart), which was marked in the coroner's report as a "significant condition" that may have played a role in the drummer's death. The Coroner's Department conducted "five or six" different tests to verify the cause of death, Sigal added.

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