LAUSR

Background: Baclofen is a GABA-B receptor agonist widely used for treatment of spasticity by intrathecal route when oral baclofen was ineffective or intolerable. Here we report a case of recurrent episodes of brief global amnesia in a patient with multiple sclerosis treated with an intrathecal baclofen pump. Case report: A 64-year old widowed white woman with multiple sclerosis was admitted for ambulatory EEG monitoring unit for a 3-year history of recurrent periods of 10-40 minutes of confused behavior, with anterograde and retrograde amnesia, but without loss of consciousness or abnormal movements. Episodes were more likely when under stress or around family events. An intrathecal baclofen pump had been placed 12 years before admission to control lower extremity spasticity. EEG monitoring demonstrated no epileptic activity during the events. Over the next 6 months intrathecal baclofen was gradually decreased, with reduced frequency of episodes. At the lowest dose episodes stopped but there was some return of spasticity. With careful titration upwards a dose was reached with adequate treatment of spasticity but no episodes. Conclusions: Intrathecal baclofen can induce brief episodes of global amnesia. This is the second reported such case, and the first to be successfully managed by dose titration. The episodes resembled those of transient global amnesia and of transient epileptic amnesia, and we review mechanisms by which baclofen can affect memory function. These episodes were initially thought to represent conversion disorder, emphasizing the caution required before postulating psychogenic etiologies of medical symptoms. Rosenblum et al 2016 3