Dialectical behavior therapy has demonstrated effectiveness for patients suffering from co-morbid borderline personality and substance use disorder. The current study tries to replicate results of previous studies in a mixed gender sample of Egyptian outpatients.

The aim of the current study was to examine the effectiveness of DBT without drug replacement relative to treatment as usual “TAU” in improving behavioral outcomes related to SUD and BPD, and improving emotional regulation.

Forty outpatients with co-morbid BPD and SUD in Alexandria and Cairo were assigned for one year either to comprehensive DBT program (20 patients), or TAU defined as ongoing outpatient psychotherapeutic treatment from referring center (20 patients). Patients were assessed at baseline and follow up assessment at 4, 8, 12 and 16 months was done using Arabic version of Difficulties in Emotion Regulation Scale (DERS), urine multidrug screen and time line follow-back method for assessment of alcohol and substance use history.

Following one year of treatment, DBT group showed significantly lower doses of drugs used, DERS score, rates of hospital admission, ER visits, suicidal attempts and episodes of NSSI. Also, DBT patients showed markedly increased retention in treatment and longer duration of total alcohol abstinence and other drugs of abuse. Positive outcomes were maintained for four months post-treatment.

DBT demonstrated superior efficacy in comparison to TAU for treatment of Egyptian patients suffering from co-morbid borderline personality and substance use disorder across behavioral domains of SUD, BPD and reduction hospital admission, emergency room visits and DERS score.