Introduction - Outbreaks of unexplained physical complaints are situations in which people exhibit the same somatic symptoms, with no organic cause, and in which these symptoms spread to others through emotional contagion. Although these phenomena are underestimated in France, they have significant implications for clinical management. To help improve their management, the main characteristics of these psychogenic syndromes are described here, highlighting the challenges encountered during investigations. Description - These phenomena manifest as nonspecific symptoms that do not strongly suggest a particular etiology, are mild in nature, and resolve rapidly within a few hours. They are observed primarily in women and adolescents, in school settings or in the workplace. In the majority of cases, the presence of a triggering anxiety-inducing factor is cited, but the factor implicated is often environmental. These episodes spread through sound and sight. Discussion - When faced with an event exhibiting the characteristics described above, it is essential to formulate a diagnosis from the outset that suggests the psychogenic nature of the event. Early intervention and a precise description of the context of the outbreak and the triggering factors can help to downplay the situation. Better information for the staff of the responding services should help avoid disproportionate intervention and inappropriate management, which fuel and reinforce collective anxiety. (R.A.)