Joan Rivers, David Letterman

Joan Rivers just got a taste of her own medicine.

Days after walking out on CNN Newsroom host Fredericka Whitfield in the middle of an interview, Rivers was on the flip side of things while appearing on The Late Show.

After explaining that Whitfield was "very judgmental, very nasty, very opinionated ... like my wedding night," Rivers told David Letterman that she was recently passed over for a Depends commercial. "While I'm talking to you, I'm taking a dump," Rivers joked of the commercial dialogue, to which Letterman promptly walked out.

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Rivers then proceeded to interview herself. "How's your sex life, you old b----?" she asked herself. "Thank you for asking. My vagina is so dry." "How dry is your vagina?" "I took a bath and all the water went whoosh."

Rivers, 81, made headlines Saturday when she walked out of a taped interview with Whitfield because the comedienne felt she was being asked "negative" questions.

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Late Show with David Letterman airs weeknights at 11:35/10:35c on CBS.

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