Allison signed with Detroit in the offseason from Green Bay, where he had 89 catches for 1,045 yards and six touchdowns from 2016 to 2019.
The Lions signed Allison, 26, to provide depth behind outside receivers Kenny Golladay and Marvin Jones. Detroit gave him a one-year, $910,000 deal with a $137,500 signing bonus when he signed.
Wide receiver is one of the deeper positions for the Lions, with Golladay, Jones and Danny Amendola likely locked in as starters.
Allison is the second Detroit player to opt out this season, joining defensive tackle John Atkins.
The Lions also claimed former Baltimore defensive tackle Daylon Mack off waivers, placed defensive end Romeo Okwara on the non-football injury list and defensive end Austin Bryant on the physically unable to perform list.