"I'm going to make sure something like this never happens again. Whatever circumstances, consequences ... whatever I have to do so this won't happen again, I'm going to do it."
Gallardo did not take questions from reporters.
"I don't know how long it's going to take to get this cleared up; the whole situation that happened," Gallardo said.
"The main thing, like I said, I came out here to apologize. Especially to the people that look up to me. Obviously, it's something that I regret. I'm going to make sure it never happens again."
Gallardo raced to the Major Leagues after starring with the Power in 2005, when he went 8-3 with a 2.74 ERA in 26 appearances (18 starts). He made his big league debut at 21 years old in 2007 and finished seventh in the National League Cy Young race in 2011.
In Wisconsin, first-offense drunken driving is a citation, not a misdemeanor or felony charge.
McLaughlin said Gallardo faces nearly $800 in fines for drunken driving and for unsafe driving.
Gallardo was a 16-game winner last season, his fourth consecutive season with at least 200 strikeouts.
He gave up six runs in a loss Saturday to St. Louis and is 0-1 in three starts this season with a 6.61 ERA. The Brewers entered Tuesday's game at 3-8, worst in the National League Central Division.