A veteran of five seasons with the San Francisco Giants and the Los Angeles Angels, Frandsen signed a minor league contract with the Phillies on April 1. He became a free agent in December when the Angels declined to offer a 2011 contract, then went to spring training with the San Diego Padres, who released him on March 25.
The commissioner's office said he tested positive for Ritalinic Acid, which essentially is the same as Ritalin, which is used to treat attention deficit hyperactivity disorder. Baseball players can obtain therapeutic use exemptions for drugs to treat ADHD, and Frandsen would not have been suspended if he had a TUE for Ritalin.
His agent, Damon Lapa, did not return a telephone call seeking comment.
The 28-year-old Frandsen had a .243 career average with seven homers and 53 RBIs. He is hitting .321 this season at the Triple-A Lehigh Valley IronPigs.
In addition, free agent outfielder Joe Dickerson was suspended for 50 games after testing positive for an amphetamine. The penalty will start after he signs with a major league organization.
There have been 24 suspensions this year under the minor league program. While there have not been any suspensions under the major league program, Manny Ramirez retired rather than face a 100-game ban following a second violation.