Risperidone-induced temporomandibular joint dislocation: a case report ayşe erdoğan kaya, muhammed nurullah sezer, çağlar turan psychiatry and clinical psychopharmacology 28, 161-162, 2018

Acute dystonia is a side effect of extrapyramidal system due to D2 receptor blockade of the antipsychotics. It is a psychiatric emergency that develops dramatically during antipsychotic treatment and generally has well response to anticholinergics. Dystonias are involuntary, continuous, or spasmodic muscle contractions that cause abnormal curves and various postures. Acute dystonia may cause severe complications in some patients due to prolonged response time to treatment. One of these complications may be temporomandibular joint dislocation. Here, we report a case of acute dystonia with temporomandibular joint dislocation after risperidone treatment.

Case presentation: A 30-year-old male patient admitted to our clinic with bipolar manic episode. Positive findings in the psychiatric examination were logorrhea, irritability, mood elevation, flight of ideas, persecutions, auditory hallucinations, reference ideas, and psychomotor agitation. According to the anamnesis, he had bipolar disorder for 2 years with previous positive response to lithium, risperidone, and quetiapine treatments. Lithium and low-dose quetiapine treatment has been started for manic symptoms. Lithium increased up to 1200 mg for effective blood level. Additionally, 4 mg risperidone was administered for psychotic symptoms. Several hours after the administration of risperidone, the patient began to have contractions of the oromandibular and cervical region muscles, asymmetry on the face and neck, dysphagia, oedema, rigidity, and bradykinesia. Risperidone treatment was stopped and 5 mg biperiden HC injection was administered immediately. Bradikinesia and rigidity remitted but dystonia did not. A second injection of biperiden was administered but oromandibular region asymmetry and swallowing difficulties were still evident and prolonged to the other day. Lorazepam2. 5 mg was added to the treatment but dystonia went on. The consultant of neurology and otorhinolaryngology was requested. Neurologist started botox treatment but no response was observed. After improving psychotic and manic