CHAPEL HILL, N.C. -- Former Olympic sprinter Antonio Pettigrew, who admitted to doping and was stripped of a gold medal, committed suicide by overdosing on a drug common to sleeping pills, according to an autopsy report released Wednesday.
Pettigrew, 42, was found dead in the backseat of his locked car in August.
An autopsy report released by the state medical examiner's office said the cause of death was diphenhydramine toxicity. Another report rules the case a suicide and the likely toxic agent as the sleep aid Unisom, which the National Institutes of Health says contains diphenhydramine.
Police and friends began searching Pettigrew's route home from work as an assistant track coach at the University of North Carolina.
"A bottle that had held 30 Unisom was in the vehicle -- a pill was loose in the vehicle," an investigative report by medical examiner Dr. Deborah Radisch said.
The report describing circumstances surrounding the death said a preliminary investigation did not show Pettigrew facing financial problems but that he was facing stress on the job.
"Antonio's death was a tragic loss for his family, friends and members of the track community, including the Carolina track and field program," UNC track coach Dennis Craddock said in a statement issued Wednesday. "Our prayers continue to be with his family and everyone who loved Antonio as they deal with that loss."
Craddock's statement made no reference to Pettigrew's job situation and he didn't immediately respond to an e-mail seeking additional comment.
Pettigrew was part of the 1,600-meter U.S. relay team that won the gold medal in the Sydney Olympics in 2000. But the International Olympic Committee stripped the team of the medals two years ago after Pettigrew admitted doping during a trial against former coach Trevor Graham, who was convicted of lying to federal investigators about his relationship to an admitted steroids dealer.
Pettigrew said in August 2008 that his actions were "100 percent wrong" and that he appreciated getting a second chance by working at UNC, where he spent four seasons.
He graduated in 1993 from St. Augustine's College in Raleigh, where he was an All-American and won four NCAA Division II championships in the 400-meter dash.