Jeffress, then with the Texas Rangers, was arrested on Aug. 26, 2016, by Dallas police.
Jeffress was sentenced to three days in jail and the judge gave him credit for the jail time already served.
Jeffress has a history of substance abuse. He was suspended for 50 games in 2007 and for 100 games in 2009, both times when he was in the minors.
The Rangers traded Jeffress, 30, to the Brewers at last year's non-waiver trade deadline. The right-hander finished a combined 5-2 with a 4.68 ERA in 65⅓ innings last season between the two clubs.
In December, Jeffress signed a one-year contract with the Brewers for the 2018 season.
Information from The Associated Press was used in this report.