Robin Williams is seeking treatment for alcoholism, publicist Mara Buxbaum said Wednesday.

The 55-year-old comedian had been sober for 20 years, Buxbaum said.

Williams "found himself drinking again and has decided to take proactive measures to deal with this for his own well-being and the well-being of his family," she said in a statement. "He looks forward to returning to work this fall to support his upcoming film releases."

Buxbaum declined to elaborate beyond the statement.

Williams stars in "Man of the Year," due in October, and voices an animated penguin in "Happy Feet," slated for release in November. His new film, "The Night Listener," is now in theaters.

He won an Oscar for his supporting role in 1997's "Good Will Hunting."