LOS ANGELES -- Former USC quarterback Mitch Mustain, arrested Tuesday night in Van Nuys on suspicion of selling prescription narcotics, will not be charged with a felony, a spokesperson for the Los Angeles County district attorney's office said Thursday.

Mustain was arrested shortly after 8 p.m. PT Tuesday after allegedly selling a substance he passed off as Adderall to an undercover officer. But the substance sold was lisdexamfetamine dimesylate, similar to Adderall but not a controlled substance and thus not punishable as a felony.

He still could have been charged with a felony because he advertised the substance as Adderall, but prosecutors opted to send the case to the Los Angeles City Attorney's office and limit the charges to a possible misdemeanor.

"Given that Mustain has no record, and that this is his first contact with law enforcement, it is appropriate that it be referred to the City Attorney's Office for misdemeanor consideration," officials wrote in a charge evaluation form Thursday.

Mustain could be charged in the case as early as next week, Los Angeles City Attorney's Office spokesman Frank Mateljan said Thursday. Mateljan said he was unaware of the details of the minimum and maximum punishments for the misdemeanor charge.

Bail in the case was originally set at $30,000 but lowered to $10,000 midway through Wednesday. Mustain spent nearly one full day in the Van Nuys Jail before he was released shortly after 6 p.m. PT Wednesday.

Mustain, 22, was preparing for the upcoming NFL draft and had been on campus at USC to work out in the school's athletic facilities late last week. He started only one game in four seasons at USC, a 20-16 home loss to Notre Dame in November, after transferring from Arkansas in 2007.

The Arkansas native was one of the most sought-after high school players in history.

Pedro Moura is a contributor for ESPNLosAngeles.com.