"Around the beginning of training camp, I made a mistake by taking an Adderall pill without a prescription," Talib said in a statement on the Buccaneers' website.
The fifth-year player will be eligible to return to Tampa Bay's active roster on November 5, the day after they play the Oakland Raiders.
Talib had started all four games for Tampa Bay (1-3) this season, intercepting one pass and making 20 tackles.
The suspension is his second in three seasons.
He was suspended for the 2010 regular-season opener and fined one additional game paycheck for violating the league's personal conduct policy following an altercation with a St. Petersburg, Florida cab driver during training camp in 2009.