Share psychotic disorder “folie à deux” is a rare condition characterized by the transmission of delusional aspects from a patient to another linked by a close relationship. We report the case of two Spanish men who have experienced a combined delusional episode induced by mephedrone.

Describe a case of share psychotic disorder induced by mephedrone. Make a review on scientific literature about the use of mephedrone (little is known about the psychiatric consequences of the use of these compounds). The patients had no psychiatric history.

Show the danger of these novel drugs that are often bought as apparently safe and legal.

Share psychotic disorder was first introduced by Lasegue and Falret who hypothesized that transmission of psychiatric disturbance from one person to another was possible under certain circumstances. The correlation of symptoms with the intake of these substances is supposed in the light of a negative psychiatric history and no other concomitant medical treatments. An important number of case reports documented deaths related to the ingestion of mephedrone. Another problem is that these substances are not detected by standard blood and urine test so that the diagnosis of intoxication is often delayed.

The authors have not supplied their declaration of competing interest.