Introduction. Due to the psychiatric comorbidity seen among cocaine addicts, it is of clinical interest to know the personality traits associated to the use of this substance. Methodology. Personality-profile comparative study of cocaine users and multiple-substance users obtained through the Multistage Personality Inventory The study analyzed a sample of 30 cocaine users and 26 users of various substances who asked for treatment at a specialized institution. Results. Results show the sane profile for both groups, with high 8-4-2 scales. According to the Multistage Personality Inventory, this profile corresponds to an antisocial personality disorder with depressive and schizoid traits. Conclusions. The fact that there is a single profile for different drug users leads us to the hypothesis that there are addictive personality characteristics rather than specific traits related to the use of each substance. These subjects' personality characteristics suggest that the fear to relate to others could make it very difficult to establish a therapeutic link. This, in addition to the acting tip tendency seen among users, constitutes a call of alert in terms of their likely abandonment of treatment. Further more, as they take impulses into actions, they, build a barrier before words. This could be called acting up,, doing instead of saying, which can become an obstacle for the appropriate development of the therapeutic process. The result must consider the size of the sample.