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.

Marshall says the NFL is so competitive that "guys try anything just to get that edge. ... I've heard crazy stories. I've heard of guys using Viagra, seriously."

Marshall says he's healthy and doesn't take any medications "of any sort."

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