Northampton County District Attorney John Morganelli released details of the investigation at a news conference and Northampton County Coroner Zachary Lysek confirmed toxicology testing had confirmed the presence of heroin in Garrett Reid's body.
The official cause of death was "acute opiate 'heroin' toxicity."
Garrett Reid -- who had a history of substance abuse -- was 29 years old when he was found dead Aug. 5 in a dormitory room at Lehigh University, where the Eagles conduct their training camp.
Andy Reid said in a statement at the time of his son's death that Garrett Reid "lost the battle that has been ongoing for the last eight years."
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