Background: This study consists of a brief psychological intervention, which uses Self- Regulation Therapy (SRT, procedure based on suggestion and classical conditioning), to improve coping with stress and emotionality by reproducing the positive effects of illegal drugs: cannabis, cocaine, ecstasy. Method: 15 volunteers (8 males, 7 females), with a mean age of 24.6 (SD = 4.4), underwent intervention to improve their coping with stress and emotionality using SRT. They carried out pre- and post-intervention scores for 10 days and during a 4-week follow-up. The employed instruments were: BSS (Barber Suggestibility Scale); COPE (Coping Skills Inventory), and PANAS (Positive and Negative Affect Schedule). Results: SRT was superior to non-intervention for the 4 coping strategies (h2 = 0.829, 0.453, 0.411 and 0.606) and for positive (h2 = 0.371) and negative emotionality (h2 = 0.419). An improvement in scores was evidenced in the follow-up scores compared to the pre-intervention measures. Conclusions: This study shows for the first time that it is possible to use illegal drugs, considered harmful to public health, to improve young people's coping capacity and emotionality by reproducing their positive effects with SRT.