Amantadine use in pediatric Catatonia: A case series

INTRODUCTION: Catatonia is a life threatening neuropsychiatric disorder. Characterized by mutism,negativism, poor oral intake and other psychomotor disturbances. Catatonia can be associated with several psychiatric and medical conditions. BFCRS is the rating scale used in the diagnosis and prognosis of catatonic symptoms. Lorazepam is the first line of treatment for catatonia followed by ECT. Because of the role of NMDA and GABA receptors in the pathophysiology of catatonia drugs like zolpidem and amantadine are gaining popularity. CASE REPORT: A 13 year old male presented with an acute illness of ten days.started with irritability crying spells and anger outburst. progressed to mutism,poor oral intake and posturing. initial investigation were found to be with in normal range.BFCRS score was 16 and diagnosis of catatonia was made.patient was given iv lorazepam challenge test. Patient showed some improvement in mutism and was started on iv inj lzm 2mg three times in a day. Only transient improvement was seen. patient was started on tab amantadine 100 mg which was increased upto 300 mg/day and lorazepam was tapered and stopped. Patient.BFCRS score reduced to 3 from 16. CASE 2: A 16 year old girl presented with illness started 15 days prior to admission. Patient started remaining withdrawn and muttering to self with inappropriate spells of laughter. progressed to decreased oral intake,rigidity,mutism and urinary incontinence. initial investigation were within normal range apart from decreased RBS. Diagnosis of catatonia was made and BFCRS score was 18. After the lorazepam challenge test patient was started on iv lorazepam which was increased upto 8 mg/day in divided doses and low dose olanzapine was also added. Patient did not show much improvement on the drugs. Patient was started on tablet amantadine and increased upto 400 mg/day in divided doses. BFCRS score was reduced to 4 from 18. CONCLUSION: Theories have focused on dysfunction of GABA and NMDA receptors in basal ganglia. imbalance in inhibitory and glutamatergic excitatory pathways result in impairment of motor planning and execution leading to motor symptoms. NMDA receptor antagonists like amantadine and memantine are currently being studied in the treatment of developmental disorders and catatonia.