Three cases of pneumomediastinum related to smoking cocaine in the form of "crack" are presented. The patients complained of chest or neck pain occurring 1 to 6 hours after smoking crack. All three did not immediately divulge a history of cocaine use. There was spontaneous resolution of pneumomediastinum in every case, and the creation of pneumomediastinum appeared to be directly related to the route of drug use. The abuse of crack and the mechanism of spontaneous pneumomediastinum are discussed.