The Stars loaned Johns to the Texas Stars of the American Hockey League on Wednesday for a conditioning assignment. The club didn't indicate how long he would be in the minors.
Johns missed all of last season with what were identified as post-traumatic headaches. The 27-year-old played his first three NHL seasons with the Stars after coming over from Chicago in a trade.
A second-round pick by the Blackhawks in 2010, Johns debuted with the Stars five years later in the first season after the trade. Johns played a career-high 75 games in the most recent season he was active, 2017-18, when the Stars went 42-32-8 with 92 points.
Johns played 14 regular-season games as a rookie in 2015-16, then was part of all 13 playoff games for the Stars, who finished that season with 109 points as the West's No. 1 seed. Dallas lost in Game 7 to St. Louis in the second round.
Johns has 28 points (13 goals, 15 assists) in 150 career regular-season games.
Dallas, which lost in the second round last season, is part of a crowded field of contenders in the Western Conference this season. The Stars, who dismissed coach Jim Montgomery earlier this season, giving the interim reins to Rick Bowness, will meet the Ducks in Anaheim on Thursday.
The Associated Press contributed to this report.