Abstract Pyoderma gangrenosum associated to the use of cocaine/levamisole is a rare condition associated to their consumption. Cocaine use is frequent in Colombia, and the substance is contaminated with levamisole, an anthelmintic that increases the psychotropic effects and enhances its side effects. We present three clinical cases of patients with ulcerated lesions, in which the diagnosis was pyoderma gangrenosum secondary to the use of cocaine contaminated with levamisole. This called the attention of the health staff to investigate the abuse of substances in gangrenous pyoderma and also evidence that the interruption of consumption was the basis of management.