Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a neuroinflammatory disease mediated by antibodies targeting the GluN1 subunit of the NMDAR. It presents with well-defined neuropsychiatric symptoms, including psychosis, agitation, seizures, and memory disturbances.¹ Movement disorders including orofacial dyskinesias are common, but often difficult to manage, with no specific published guidelines.^1,2,3

A 23-year-old female was diagnosed with NMDAR encephalitis. She was treated with ovarian teratoma removal, corticosteroids, intravenous immunoglobulin therapy, rituximab, and tocilizumab. She continued to experience severe, self-mutilating orofacial dyskinesias. Tetrabenazine, haloperidol, and diazepam did not yield any sustained improvement. Tramadol was started based on prior case reports suggesting its efficacy as well as clonazepam.³

Tramadol 50 mg po q6h led to immediate improvement in symptoms. Over the next 5 days, tramadol was increased to 150mg NG q6h and further reduced movements. When tramadol was held for one day, the movements significantly worsened and improved when it was restarted. Clonazepam 1mg NG QID also led to further improvement.

Tramadol and clonazepam effectively treated severe orofacial dyskinesias in a patient with NMDAR encephalitis and refractory symptoms despite aggressive management. We propose early use of tramadol and clonazepam be considered for severe orofacial dyskinesias secondary to NMDAR encephalitis.  

References:

1. Dalmau. (2016). NMDA receptor encephalitis and other antibody-mediated disorders of the synapse: The 2016 Cotzias Lecture.Neurology,87(23), 2471–2482.
2. Huang, Xie, Y., Hu, Z., & Tang, X. (2020). Anti-N-methyl-D-aspartate receptor encephalitis: A review of pathogenic mechanisms, treatment, prognosis.Brain Research,1727, 146549–146549.
3. Ho KM. Use of tramadol to attenuate severe dyskinesia in anti-N-methyl-D-aspartate receptor encephalitis. Anaesthesia and Intensive Care. 2019;47(6):561-562.