Youth drug use is a severe problem worldwide. Usage of cannabis, amphetamine ecstasy and cocaine, referred to here as non-opioid drugs, are strongly associated with a range of health and social problems. Functional Family Therapy (FFT) is a short-term, manual-based, behaviorally oriented family therapy program for young people with behavior problems such as drug abuse, juvenile delinquency and violence. Delivered in an outpatient setting, it aims to help young people and their families by improving family interactions and relationship functioning by addressing dysfunctional individual behavior. As with many other forms of family therapy, FFT targets young people and their families as a system. As such, it recognizes the important role of the family system in the development and treatment of young people’s drug abuse problems.

The main aim of this review is to evaluate the current evidence on the effects of FFT on drug abuse reduction for young people in treatment for non-opioid drug use.

The literature search yielded a total of 6,719 records, which were screened for eligibility based on title and abstract. From these, 108 potentially relevant records were retrieved and screened in full text, of which 9 records were potentially relevant. Finally, two studies based on three records were included in the review. Meta-analysis was not possible because only one study provided numerical results on the effect of FFT on drug use reduction.

Two studies were included and both analyzed relative effects, comparing FFT to other interventions. Only one study provided numerical results on drug use reduction comparing FFT to two other interventions (CBT and a group intervention). The reported results indicate a positive effect favoring FFT on drug use frequency at 4-month follow up, with no statistically significant difference at 7-month follow up.

There is insufficient firm evidence to allow any conclusion to be drawn on the effect of FFT for young people in treatment for non-opioid drug use. There is a need for more research, and particularly for more methodologically rigorous studies in the field of treatment for young drug users. The aim of this systematic review was to explore what is known about the effectiveness of FFT for the purpose of reducing youth drug use. The evidence found does not provide a basis for drawing conclusions about actual outcomes and impacts. Consequently, no substantive conclusion on the effectiveness can be made, neither supporting nor rejecting of the present FFT treatment approach.