Chronic Pregabalin Abuse with Subacute Encephalopathy Mimicking Autoimmune Encephalitis.

Pregabalin, a gabapentinoid frequently prescribed for neuropathic pain, also increasingly identified as a drug for abuse. We describe a unique case of 31-year-old man presented with subacute neuro-psychiatric symptoms and a spectrum of movement disorders, suspicious of autoimmune encephalitis. Initial response to IV methylprednisolone followed by recurrence of symptoms strengthened our suspicion for autoimmune encephalitis. His autoimmune encephalitis workup was negative, however, his two MRIs showed parenchymal changes. The patient, finally, confessed to chronic pregabalin abuse. He recovered completely upon stopping pregabalin abuse and remained asymptomatic at follow-up. To the best of our knowledge, we are the first to describe parenchymal changes in MRI mimicking autoimmune encephalitis in a case of pregabalin abuse. Despite the limited number of reports of pregabalin abuse in India, it is time to consider restricting the pregabalin availability, in line with many Western countries. This is particularly relevant to India, where, one legitimate prescription can be used by many to buy medicines at multiple stores without any questions being asked by the pharmacists.