Functional Movement Disorder and Parkinson’s Disease Comorbidity: A Case Report

Overview

Case Presentation

A 22-year-old male patient presented to the emergency room of hospital with chief complaints of restlessness, an intolerable urge to pace around, suspiciousness, and sleep disturbances in the form of late-onset and midnight awakenings for four days.

Medical History

  • Upon eliciting a detailed history, it was established that a couple of weeks ago, he was taken to the psychiatrist with a history of suspiciousness, disorganized behavior in the form of muttering to self and poor self-care, withdrawn behavior, and sleep disturbances in the form of late-onset and midnight awakenings since one month.
  • His brother reported a change in the patient’s behavior in the past few months, being suspicious and withdrawn as opposed to his premorbid extrovert personality.
  • There was a history of daily cannabis consumption by the patient, with the last consumption being over two years ago, along with occasional consumption of alcohol and tobacco chewing.
  • At initial presentation, the patient denied any illness, which was indicative of poor insight. After an adequate assessment, the patient was diagnosed with schizophrenia
  • He was started on olanzapine at 2.5 mg/day on the first day by a private psychiatrist.
  • This was subsequently increased to 5 mg/day on day 3.
  • At this juncture, the patient reported episodes of mild restlessness, which did not interfere with the patient’s daily activities but caused discomfort.
  • To counter this, propranolol 20 mg/day was added on day 3. Olanzapine was further increased to 15 mg/day on day 5 to relieve psychotic symptoms.
  • Six days after maintaining the dose at 15 mg/day, he developed extrapyramidal symptoms in the form of tremors, slowness of movement, decreased arm swing while walking, and mask-like faces. This was followed by subjective reporting of severe restlessness along with objective evidence of akathisia since day 10.
  • On day 14, the patient was referred to the hospital due to the gradual worsening of the above complaints and was admitted for further management.

Family History

  • The patient’s heredity was not burdened by mental disorders

Clinical Exam

  • Physical examination of the patient at the time of admission revealed a positive glabellar tap sign.
  • A diagnosis of drug-induced parkinsonism (DIP) and akathisia was made.

Treatment

  • For the disabling akathisia, the patient was continued on propranolol 20 mg/day and clonazepam 1 mg/day was added, while trihexyphenidyl 3 mg/day (2 mg tablet as 1-1/2) was added to treat the DIP
  • Risperidone was given in equally divided doses twice daily

Clinical Outcome

  • After one week, the akathisia and DIP completely subsided, and he was maintained on risperidone at 8 mg/day.
  • Clonazepam was reduced to 0.75 mg per day on day 28.

Careful observation, interviews, and periodic mental status examinations revealed no DIP or akathisia but good clinical improvement in psychotic symptoms and the patient was discharged on day 30 of admission.

Adapted from:

  1. Jaitpal V, Gawande S. Olanzapine-Induced Parkinsonism and Akathisia: A Case Report. Cureus. 2022;14(1):e21354. Published 2022 Jan 18. doi:10.7759/cureus.21354.