The Ducks made the move after backup goalie Jonathan Bernier was injured in a loss at San Jose on Tuesday.
Bernier has an upper-body muscle injury, the team said. Regular starter John Gibson replaced him for the final two periods and overtime in the 2-1 loss.
Bernier has played four periods in his first season with Anaheim, going 0-1-0 with a 3.04 goals-against average.
The Ducks acquired Tokarski in a trade with Montreal in January, but he has yet to play for Anaheim, spending his time in San Diego. The former Tampa Bay draft pick played in 26 regular-season games and five playoff games for the Canadiens over three seasons.
Anaheim will host Nashville on Wednesday.