Stone is out with a blood clot and has no timetable for a return. Frolik has a lower-body injury.
Stone has four assists in 11 games this season but has played one game since Oct. 25.
"He's dealing with a blood clot, those are serious and significant," Calgary general manager Brad Treliving said. "There's no timeline right now. He's under the care of our medical staff and they're dealing with that.
"He practiced yesterday and was feeling some discomfort last night, came in this morning. Obviously when we found about it, we wanted to get him in right away this morning to get it looked at and rule some stuff out."
Frolik has seven goals in 20 games this season. He did not play in the past two games and will not travel with the Flames on their upcoming two-game road trip, which begins against Vegas Golden Knights on Friday (6 p.m. ET; SN1, ATTSN-RM, SNW, ATTSN-RM, NHL.TV).
The Flames recalled forward
Ryan Lomberg
and defenseman
Oliver Kylington
from Stockton of the Amercan Hockey League.
Forward Sam Bennett had a maintenance day Thursday but Treliving said he is expected to play against Vegas.
