He's in therapy for his use of an anti-gay slur against a castmate.
"With the support of my family and friends, I have begun counseling. I regard this as a necessary step toward understanding why I did what I did and making sure it never happens again," Washington said in a statement Wednesday. "I appreciate the fact that I have been given this opportunity and I remain committed to transforming my negative actions into positive results, personally and professionally."
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Washington took a break from filming Tuesday to meet with gay rights activists and offer help in educating the public about the cruelty of such words, an offer the activists called sincere.
Whether Washington was receiving outpatient counseling or had entered a facility was not specified, and the statement did not indicate whether he would miss work on the show.
Washington's publicist, Kelly Mullens, declined to comment further. A call to ABC about the effect on production of the hit TV show was not immediately returned Wednesday.
Series creator and executive producer Shonda Rhimes issued her own statement, at once criticizing Washington for his use of the word "faggot" about co-star T.R. Knight and lauding Washington's decision to seek help.
"I speak for all the executive producers here at 'Grey's Anatomy' when I say that Isaiah Washington's use of such a disturbing word was a shocking and dismaying event that insulted not only gays and lesbians everywhere, but anyone who has ever struggled for respect in a world that is not always accepting of difference," Rhimes said.
She said she's been working within "the 'Grey's family" and with ABC and the Touchstone Television studio to address the issue "in a way that underscores the gravity of the situation while giving us all a foundation for healing."
"We applaud and encourage Isaiah's realization that he needs help and his subsequent choice to seek immediate treatment for his behavioral issues," Rhimes said.
She expressed appreciation to fans during this "stressful time" and said those involved with the show would continue to "make the best television we can."
It was during an on-set quarrel last October with co-star Patrick Dempsey that Washington reportedly used the slur about Knight, who was not present. Although Washington apologized publicly at the time, the issue boiled up again at the Jan. 15 Golden Globes when he denied using the epithet.
After being criticized last week by the Gay & Lesbian Alliance Against Defamation and ABC, Washington issued an apology.
He met Tuesday with the heads of GLAAD and Gay, Lesbian and Straight Education Network, who said Washington agreed to efforts to fight bias but that no specifics were reached.
ABC and Touchstone Television are owned by Walt Disney Co.
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