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CHICAGO (AP) — Bears wide receiver Brandon Marshall says he has heard of players using Viagra in an effort to gain an edge on the field.

Marshall made the comment Wednesday when he was asked about a growing number of suspensions tied to amphetamines, including the ADHD drug Adderall.

Marshall said he didn’t know much about Adderall, but then suggested Viagra, which is used to treat impotence in men, could be seen by players as a way to boost their energy.

“I know guys, it’s such competitive league and guys try anything just to get that edge,” he said. “I’ve heard of guys using Viagra, seriously, because the blood, it’s supposed to thin . I don’t know. Some crazy stuff. It’s kind of scary with some of these chemicals that are in some of these things, so you have to be careful.”

Marshall said he doesn’t take medication “of any sort” and noted that the NFL’s drug policy is strict.

“Any time you take anything over the counter, if you don’t approve it with your training room, you can get popped,” he said. “Some of it’s fair, but some of it kind of puts you in a tough spot as a professional athlete. Because the only thing you’ll see is getting busted for PEDs, but it could be something over the counter for a little sickness. You just have to be on top of your Ps and Qs.

NFL spokesman Greg Aiello said Viagra is not a banned substance and declined further comment.

Since the start of last season, more than 10 players suspended for failing drug tests have publicly blamed it on taking Adderall, a stimulant experts say could provide a competitive advantage by increasing concentration and possibly aggression.

But an impotence drug? Bears offensive coordinator Mike Tice seemed surprised by Marshall’s comment.

“Viagra?” he said. “I’ve never heard of such a thing. He’s making that up. He’s got to be making that up. You’ve got to be kidding me.”

Copyright 2012 The Associated Press.