Last Updated Nov 20, 2013 11:20 PM EST
Rep. Henry "Trey" Radel announced Wednesday night that he was taking a leave of absence and entering a treatment program, hours after he pleaded guilty to possession of cocaine.
At a news conference, an emotional Radel said he would donate his salary to charity while he is away from Congress.
"I'm struggling with this disease, but I can overcome it," the Florida Republican said.
The freshman congressman said he realized he had let down the country, his constituents and his family.
"I want to be a better man," said Radel, who said he would enter an intensive in-patient program to get treatment for substance abuse.
Earlier Wednesday, Radel was sentenced to a year of minimally supervised probation and ordered to pay a $250 fine to a victims' compensation fund after pleading guilty Wednesday to the possession of cocaine.
"I apologize for what I have done," Radel said in court earlier Wednesday. "I am so sorry to be here."
If he violates his probation, he faces up to 180 days in jail.
After the news about his arrest came to light Tuesday evening, Radel issued a statement saying he is "profoundly sorry."
"I struggle with the disease of alcoholism, and this led to an extremely irresponsible choice," said Radel, who's serving his first term in the U.S. House. "Believe me, I am disappointed in myself, and I stand ready to face the consequences of my actions.
"However, this unfortunate event does have a positive side: It offers me an opportunity to seek treatment and counseling," he went on, requesting prayers for his family. "As the father of a young son and a husband to a loving wife, I need to get help so I can be a better man for both of them."
CBS News has learned Radel met with House Speaker John Boehner, R-Ohio, on Tuesday just before the news broke of his arrest. Afterward, a Boehner spokesman said, "Members of Congress should be held to the highest standards, and the alleged crime will be handled by the courts. Beyond that, this is between Rep. Radel, his family, and his constituents."
"Today's guilty plea emerges from a broader narcotics investigation that brought to light information that a sitting member of Congress was routinely using and buying cocaine. Once this information was confirmed, law enforcement could not ignore this illegal conduct," said U.S. Attorney Ronald Machen. "Mr. Radel's guilty plea is similar to those entered every year by hundreds of other drug offenders in the District of Columbia who possess illegal narcotics. We appreciate his willingness to promptly accept responsibility for his conduct."
Somewhat ironically, Radel is the cosponsor of H.R. 1695, Justice Safety Valve Act of 2013, which would give judges more flexibility on sentencing in cases involving mandatory minimums. He's also gone on record as citing his favorite vacation spot as Cartagena, Colombia, which as of 2004 accounted for 80 percent of the world's cocaine production.
Radel, 37, is a former television news anchor and conservative radio talk show host and represents southwest Florida. His election last year marked his first foray into politics.
Lindsey Boerma contributed to this story.