The moves were made Tuesday, before the last-place Sabres (21-48-9) hosted the Detroit Red Wings (37-27-14).
Makarov takes over the backup spot behind Matt Hackett after Nathan Lieuwen sustained a concussion in a 5-2 loss at Philadelphia on Sunday. He becomes the eighth goalie to dress for the Sabres this season.
Makarov has a 3-3 record with AHL Rochester, after opening the season in the ECHL.
Pysyk will fill in for Chad Ruhwedel, who also sustained a concussion against the Flyers. Defenceman Christian Ehrhoff's status is uncertain after he was struck in the ear by a puck against Philadelphia.
Buffalo also demoted forward Luke Adam to Rochester.