Seahawks cornerback Richard Sherman, who got in trouble last season when he allegedly tested positive for Adderall, says the prescription stimulant is a lot more prevalent in the NFL than most people may have thought.

“About half the league takes it and the league has to allow it,” Sherman told The Vancouver Sun on Tuesday. Presumably he meant half of NFL players have a prescription for Adderall and hence use it within the league’s rules on banned substances.

Last November, as the Seahawks were starting their wild run to the playoffs, the NFL said Sherman and fellow Seattle CB Brandon Browner tested positive for a performance-enhancing drug that turned out to be Adderall. Browner served a four-game suspension, but Sherman successfully appealed the league and avoided suspension.

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