bill kostroun/associated press

Jermaine Cunningham, who has made great progress in 2012, is the second Patriot suspended for PEDs this season.

By Shalise Manza Young Globe Staff

FOXBOROUGH — The Patriots’ defensive line depth took a hit Monday when the NFL announced that Jermaine Cunningham has been suspended four games without pay for violation of the league’s policy on performance-enhancing substances.

According to a league source, Cunningham tested positive for Adderall, which is commonly prescribed to individuals with attention deficit hyperactivity disorder (ADHD) or attention deficit disorder (ADD).

However, the league does not announce which substance triggered the failed test, so players can say it was for whatever they choose; since the 2012 season began, the NFL has suspended two dozen players for violation of its PED policy, and many of those players have blamed Adderall.

Under league rules, if a player is documented as requiring the drug, and has a prescription and a therapeutic use exemption for Adderall, then he can use it without penalty. Without those things, he is subject to suspension for one failed test.

Cunningham is the second Patriots player this month to be suspended for PEDs, following rookie running back Brandon Bolden. Linebacker Brandon Spikes was suspended for the last four games of the 2010 season, when he was a rookie.

And new Patriots cornerback Aqib Talib received a PED suspension while still a member of the Buccaneers, and was unable to join the Patriots until Nov. 12, more than a week after he was traded to New England, because of the suspension.