Lange was one of the original nine castmembers of MADtv when the series debuted in 1995. Unlike some of his fellow castmembers on MADtv, Lange came to the show with limited sketch comedy experience as a stand-up comedian. Around this time he became heavily involved with drugs, particularly cocaine. He has stated that his lowest point of cocaine use occurred during a shooting of the MADtv sketch “Babewatch” (a parody of Baywatch) in which he played a pig lifeguard. Because the sketch involved going through hours of make-up to transform him into a pig, he snorted cocaine in his car in full pig make-up during a break in the shooting of the sketch. Upon returning from the shoot, he passed out in his hotel room, and awoke to find he had defecated in his bed. (The cast and fanbase of The Howard Stern Show now refer to this incident as “The Pig Story.”) His tenure with MADtv came to a dramatic end when, during a cocaine binge, the police were called to the studio. Lange fled, running through a number of backyards and stores before being arrested. He was charged with cocaine possession, assaulting an officer, and possessing an open alcoholic container in his car, among other charges. Upon Lange’s arrest, Quincy Jones, an executive producer of MADtv, intervened and arranged for him to continue on the show for a second season. Lange’s sobriety did not last, however, and he was fired after two seasons.

Lange performed as a few recurring characters on the show, such as “That’s My White Momma,” but was mostly used for impressions. Among the people he imitated were Yassir Arafat, F. Lee Bailey, Roseanne Barr, George Clooney, Larry Csonka, Newt Gingrich, Ed Harris, Richard Karn, Wayne Knight, Rush Limbaugh, Ed McMahon, Rosie O’Donnell, and Joe Pesci.

Lange appeared in an episode during the show’s tenth season.