The league announced the suspension Tuesday. He will begin the suspension immediately and will be eligible to rejoin Seattle's active roster Dec. 17.
Guy's agent, Greg Linton, says the positive test was the result of an ingredient found in an over-the-counter supplement that his client took. He says Guy has no intentions of appealing his suspension and called it an innocent mistake.
Guy, a sixth-round pick out of Kentucky, has been active for only two of 10 games this season.