Patient's outgroup socialization may be a problem in the psychotherapeutic group functioning. Disadvantages – and even benefits – of this common issue in psychotherapy have been described (Vinogradov S., Yalom I.). However, the impact of new social networks – that facilitate other ways of immediate and easy communication – on this phenomenon is still unknown.

To explore the risks of spontaneous “self-help groups” supported by new technologies for the psychotherapeutic group functioning.

Course description of a psychotherapeutic group, composed by patients with eating disorders (bulimia nervosa and binge eating disorder) in the context of a specialized hospital day.

A patient – who has recently had a breakup – asked help to the group through a non-reported whatsapp chat. Gradually, patients used this new channel to express distress and daily interpersonal difficulties, showing less implication in the supervised group sessions. The patient presented a symptomatic relapse with self-harm injuries and severe eating symptoms. Finally, she left the therapy and, in the next weeks, other patients also left the group, due to different reasons, in a “drag phenomenon”. The analysis showed that the formation of this outgroup socialization changed the relationships between members and new roles were taken.

It is necessary to early address the formation of outgroup socialization in the pre-group interview, emphasizing its high risk for the future group functioning. Therapists should consider that out-group communication is common and easy due to new technologies, so the use of specific questionnaires about this issue may prevent or detect pathological events.

The authors have not supplied their declaration of competing interest.