This study explored the characteristics of a representative sample of patients who were addicted to either alcohol or cocaine, comparing the profiles of both types of drug users. A sample of 234 addicted patients (109 alcoholics and 125 cocaine addicts) who sought outpatient treatment in a Spanish clinical centre was assessed. Data on socio-demographic, consumption, psychopathological and maladjustment characteristics were collected using the European Addiction Severity Index (EuropASI), the Symptom Checklist-90-Revised (SCL-90-R) and the Millon Clinical Multiaxial Inventory (MCMI-II). Demographically, differences were observed with regard to age (alcoholics were older than cocaine addicts; t = 12.2, p = .001), employment (the alcoholic group had more labor problems; χ2= 6.2, p = .045) and family consequences (worse in alcoholics; t = 2.3, p = .025). The EuropASI results showed statistically significant differences in addiction severity, with alcoholics showing a greater severity than cocaine addicts. In terms of psychopathology, alcoholics presented more associated symptomatology than cocaine addicts. According to these results, patients with alcohol dependence have a different profile from patients with cocaine dependence, resulting in different repercussions for important areas of their lives. These differences should be taken into account when standard treatments for addiction are implemented.