During the exchange on Tuesday, Schlessinger told a caller she was "hypersensitive" for complaining of racist comments from her husband's friends.
She said "black guys say it all the time" and went on to repeat the N-word several times.
When the caller objected, Schlessinger replied: "Oh, then I guess you don't watch HBO or listen to any black comedians."
Schlessinger also said that if the caller did not have a sense of humor about race, she shouldn't have entered into an interracial marriage.
She said she "realized I had made a horrible mistake, and was so upset, I could not finish the show."
Schlessinger said she pulled herself off the air at the end of the hour.
The Associated Press contributed to this story.