Football Teams Use Painkiller Despite Risks And now, we have an abc news investigation about college football players and injections of a powerful painkiller. One star college player says it gave him a heart attack. Abc's chief investigative correspondent brian ross tells us more. Reporter: Even when he showed up in severe pain, number 94, usc defensive lineman armond armstead was told his team needed him on the field. That's what's expected you on the field, especially at usc where football is so important. Reporter: So, armstead was soon introduced to what an abc news investigation found is the closely held secret of college football training rooms. Where team doctors inject powerful prescription painkillers to get injured players back on the field. Just go in, he would give me the shot and I'd be on my way. Reporter: Medical records show armstead received injections on game day of the generic version of the painkiller toradol, developed for use in treating post operative pain in hospitals. Its label warns of the increased risk of cardiac infarction, a heart attack, and stroke, which could be fatal. And you had a heart attack? I had a heart attack. Reporter: Armstead's story has helped to shed new light on the secret world of painkillers in college football. Of the top college football teams contacted by abc news, 16 refused to disclose whether they use toradol. Six said they do not. Four said they do. Unlike professional sports, the ncaa does not keep track of the use of toradol or other painkillers. If we keep track of what happens, let's say, to horses in horse racing, don't we owe it to the athletes to keep track of what's going on in college sports? Reporter: With the backing of his parents, the 290-pound armstead, a picture of health, with no family history of heart disease, is now suing usc and the team doctor, claiming they ignored the stated risk of toradol and never told him about them. As a mom, that was an atrocity. How many other kids are going to take those shots to get on that field, not knowing, this could Reporter: The team doctor, james taboni, would not talk about whether he had revealed the risk of toradol. I can't comment on that. Reporter: You feel it's appropriate to use -- young, healthy people, we still use its. Reporter: Usc declined to comment. And when we went to the school stadium to see the coach, we were told we did not have the proper paperwork and escorted off the property. You guys are obviously making us uncomfortable. Reporter: The coach later told us he had noa until we told him about the possible risk of the painkiller. But now, at least two teams, nebraska and oklahoma, told us, they are stopped using toradol in the weight of growing concerns about the risk of the painkiller which include possible kidney failure and internal bleeding, diane. A big list there. And I know you'll have more on all of this on "nightline" tonight. We'll be watching.