The illicit drugs currently being distributed across European countries under street- name “crack” contain to a large extent alkaloids derived from cocaine and later on were classified as stimulant drug. However this same street name prevalent in Iran seemingly have no stimulant effects but sort of opioids being produced in clandestine laboratories likely to be made of heroin. In current study we carried out an analysis on illicit drugs under street name of crack discovered and confiscated by Iranian law enforcement police in Arak city in 2009 to make its true formulation clear.