Florida Rep. Trey Radel announces he will be taking a leave of absence after pleading guilty to cocaine possession.

Rep. Trey Radel, R-Fla., who earlier in the day pleaded guilty to misdemeanor possession of a controlled substance, announced Wednesday night he would be taking a leave of absence to get “intensive in-patient treatment.”

“I have no excuse for what I’ve done,” a visibly shaken Radel said at a news conference. “I have let down our country, I have let down our constituents, I have let down my family, including my wife, and, even though he doesn’t know it, I have let down my 2-year-old son.”

Radel was arrested in late October for trying to purchase cocaine, and news of his arrest became public on Tuesday.

He appeared in court on Wednesday morning, where he was sentenced to a year of probation.

A first-term congressman from south Florida, Radel said in a statement that he "struggle[s] with the disease of alcoholism, and this led to an extremely irresponsible choice."

The congressman also said he intended to seek treatment and counseling.

During his leave of absence, Radel said he would donate his salary to a charitable organization. He said he hoped to become a role model for millions of people struggling with addiction.

“I hope to come out of this a stronger man, a better man, for all of you,” he said Wednesday night.

According to Republican aides, Radel first notified House Speaker John Boehner, R-Ohio, of his arrest shortly before news regarding it broke on Tuesday.

Radel missed all four votes that have occurred this week, two on Monday and two on Tuesday. Radel did vote on the day of his arrest (a Tuesday), and also voted the following day.

NBC News' Pete Williams and Frank Thorp contributed reporting.