The talented flanker is reportedly suffered from a damaged rib cartilage and is being assessed by the Ulster medical team.
He has made the breakthrough into the Ulster side this season, with the recent defeat to Munster at Musgrave Park being his tenth Magners League cap.
A current member of the IRFU's High Performance Select Group, Pollock skippered the Irish Under-20s to a Six Nations and Grand Slam double last year.
The rib damage could see him sidelined for the rest of the season, meaning he would miss relegation-threatened Dungannon's final AIB League game against Ballymena and Ulster's Magners League run-in.
Selected in the Ireland 'A' squad for their February games against England Saxons and Scotland 'A', playing in this summer's Barclays Churchill Cup tournament would also be a target for the Omagh-born forward.