I Feel Sick is a comic book created by artist Jhonen Vasquez, with colors by Rosearik Rikki Simons. Published in August 1999 through May 2000, it is a spin-off of Vasquez's comic book series Johnny the Homicidal Maniac. I Feel Sick revolves around Devi D, a graphic designer who must face the same supernatural and psychological forces that drove Johnny C. to lunacy.

Jhonen C. Vasquez is an American cartoonist, writer, producer, and director. He is best known for creating the Johnny the Homicidal Maniac comic book series and the Nickelodeon animated series Invader Zim.