The 24-year-old was a regular in the Reds' promotion side last season but, after starting this Championship campaign in the team, he has barely featured under new head coach Gerhard Struber.
McGeehan's last appearances for the Reds were as a substitute at Middlesbrough in November and at home to QPR last month but he has not been in the last five matchday squads.
After signing in 2017, McGeehan has scored nine goals in 68 appearances for Barnsley who gave him a new contract last summer which is due to expire in 2021.
Barnsley are due to visit Portsmouth in the fourth round of the FA Cup later this month but McGeehan will not be able to play against his parent club.
Struber has spoken of his desire to trim down the squad and the likes of Mamadou Thiam, Dimitri Cavare and Dani Pinillos could also leave the club during this month's transfer window.