Epidemiological studies on dual pathology reveal that these patients have less adherence to treatment and worse evolution than non-dual patients. However, most of the studies come from mental health centers and not from addiction centers, and local studies are scarce. Our purpose was to compare the continuity in the treatment for addiction between patients with and without associated psychosis. A retrospective, observational, longitudinal and analytical review of the clinical records of the patients we attended in the hospital over a year was conducted. We found a continuity of treatment in patients with psychotic disorder associated with the 1st, 3rd and 6th month, 70%, 44.44% and 22.22% respectively and 69%, 32.71 % and 14.84% in patients without psychosis. The differences observed in the greater continuity in the treatment in patients with psychosis are not statistically significant (p = 0.91, p = 0.86 and p = 0.53 at the 1st, 3rd and 6th month, respectively). Contrary to the current bibliography in dual pathology, in our clinical experience, psychotic patients with substance dependence disorders have no less continuity in treatment than non-psychotic patients.