Ravens: Lewis report won't be a distraction

The 49ers also find the story hard to believe.

"I don't think Ray would take any substance," San Francisco tight end Vernon Davis said.

Lewis and the Ravens have been taught not to take any medication or drug without first getting the OK from the league or the team's training staff.

"I will run everything by my trainers to make sure it's legal by the NFL," cornerback Corey Graham said. "As an NFL player and a professional athlete, you do try a lot of stuff. I'm not going to sit here and say you don't. But you do have to run it by your trainers and people who know what's legal and not legal before you try it."

Linebacker Paul Kruger said he learned of the league's policy on drugs during his first season in the NFL.

"If there is something you're interested in taking, you have to make sure it's cleared and OK," he said. "From what I recall from the rookie symposium, the best way is to take it to the trainer and see what they think."

Williams said if he is interested in taking something, he'll check with the NFLPA.

"They run it for banned substances and have people there for us to check everything," Williams said. "They'll send me back an email telling me everything is cleared. That said, you're still responsible for everything you put in your body."