The 29-year-old "Rizzoli & Isles" star was taking medication for bipolar disorder and depression when he killed himself. However, no traces of opiates, alcohol, cocaine or other drugs were found in his system, the New York Daily News reported.
Young shot himself in the right temple while sitting on the couch of his North Hollywood apartment. His body was discovered Aug. 19 after he failed to show up for work.
The actor's specific motive remains unclear, the Daily News said.
The South Carolina native got his big break in acting on the Disney Channel series "The Famous Jett Jackson."
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