Florida Rep. Henry "Trey" Radel is being charged with cocaine possession and faces arraignment on Wednesday in Washington, D.C.
Authorities say the freshman Republican was found in possession of cocaine on Oct. 29, a misdemeanor offense, but provided no other details.
NPR's Tamara Keith says the charge carries a statutory maximum sentence of 180 days of imprisonment and/or a fine of $1,000.
Radel, 37, represents Florida's 19th District, which covers parts of the Gulf Coast, Fort Myers and Naples.
He issued the following statement:
"I'm profoundly sorry to let down my family, particularly my wife and son, and the people of Southwest Florida. I struggle with the disease of alcoholism, and this led to an extremely irresponsible choice. 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."
"In facing this charge, I realize the disappointment my family, friends and constituents must feel. 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. I know I have a problem and will do whatever is necessary to overcome it, hopefully setting an example for others struggling with this disease."
"Please keep my family in your prayers."