The former "D-List" star and Bravo talk show host said on HuffPost Live that Seinfeld once sent her a package and letter that gave her "instant diarrhea."
The "nasty note" was Seinfeld's response to her first Comedy Central stand-up special, during which Griffin made jokes at the sitcom icon's expense after appearing on a 1996 episode of the popular sitcom.
"I got a call from my then-agent, and they said there's a package and a letter from Jerry Seinfeld. And I got instant diarrhea. I mean, I made it to the bathroom, but just barely," Griffin joked. "To this day, he brags about how he had his staff compose this hilariously insulting letter about when he had to watch someone really talk smack on him on TV."
Griffin told Huffington Post correspondent Caitlyn Becker that Seinfeld made it into her act because he was "very rude." But she was completely caught off guard by his response because "Seinfeld" co-creator Larry David assured her Seinfeld would never see her special "in a million years."
It all worked out for the best, though, since Griffin's stand-up routine inspired "Seinfeld" writers to give her another gig.
"Then they wrote a second episode for me. My character then became a stand-up comedian who made her living talking smack about Jerry Seinfeld."
Take a trip down memory lane by watching Griffin's anti-"Seinfeld" routine and her second appearance, below: