McGloin suffered a seizure and a possible concussion, the player's father, Paul McGloin told The Patriot-News of Harrisburg.
McGloin fell and struck his head on a hard surface after a locker room confrontation with backup receiver Curtis Drake, the sources told Fight On State.
The sources said McGloin was taken from the scene on a stretcher. He was treated at nearby Mount Nittany Medical Center and released, and as of late Saturday afternoon was back at his on-campus apartment.
In an email release Saturday night, Penn State Police confirmed that they were called to the Nittany Lions' Lasch Football Building earlier in the day to investigate the report of a fight between Drake and McGloin. The release confirmed that McGloin had been treated and released from the hospital.
"Campus police and Penn State's Office of Judicial Affairs will investigate the incident and report results as they would for any other student involved in an incident on campus," the release concluded.
The Patriot-News of Harrisburg, citing information from McGloin's parents, said the quarterback suffered a seizure and probable concussion.
His status for the Nittany Lions' Jan. 2 matchup with Houston in the TicketCity Bowl in Dallas is unclear.
The incident caused interim head coach Tom Bradley to call an emergency squad meeting at the Lasch Football Building at 4:30 p.m. Most players declined comment on their way into the building for the meeting.
The meeting lasted about 15 minutes. As players filed out of the building, a representative of Penn State's Athletics Communications staff stood watch to make sure no interviews were conducted.
Drake attended the meeting. McGloin did not.
Linebacker Mike Mauti, McGloin's roommate, left the building long after most of his teammates. He told several media outlets that McGloin had indeed been hospitalized but had since returned to their apartment and was fine.
Bradley did not reply to requests for comment on the situation.
Meanwhile, co-defensive coordinator Ron Vanderlinden was asked about the situation on his way out of the building.
It's good to be a Nittany Lion, is all he would say.