Houser's unavailability makes it unclear who will start or even serve as Buffalo's backup Saturday when the team opens a three-game western road swing at Arizona.
Season-opening starter Craig Anderson and backup Dustin Tokarski are traveling with the team but have yet to be cleared to play, leaving open the possibility that the Sabres will have to sign another goalie.
Anderson resumed skating with the team this week after missing 32 games with an upper-body injury. Tokarski has missed 20 games while recovering from COVID-19.
The Sabres had signed Houser to an NHL contract two weeks ago after he was playing on a minor league deal in the team's farm system.