Parasomnia with rhythmic movements manifesting as nocturnal tongue biting.

The case of a healthy 2-year-old girl with repeated nocturnal tongue biting as a result of rhythmic movements of the jaw associated with body rocking in non-REM sleep is described. Parasomnias manifesting with rhythmic, stereotyped movements of the head, trunk and extremities are well described in healthy children. The term rhythmic movement disorders (RMD) was introduced for these repetive movements in sleep which may appear as head banging (jactatio capitis), body rocking or leg rolling. Severe injuries including fractures, subdural effusions and eye injures are reported. Repeated tongue injuries have not been described as a consequence of RMD. The differential diagnosis from nocturnal seizures is crucial to avoid overtreatment of this benign albeit dramatically presenting condition.