Autism Spectrum Disorder (ASD) is a pervasive neurodevelopmental disorder with varying phenotypic expressions that can cause significant social, communication and behavioral difficulties. The etiology of ASD is multifactorial, however, the exact underpinnings are not well understood. It is suggested that glutamate excitotoxicity may be a contributing factor to the pathogenesis of ASD (1-3). Given the potential role of glutamate dysregulation in ASD, there is a growing body of research investigating the efficacy of Memantine, a N-methylD-aspartic acid (NMDA) glutamate receptor antagonist in the treatment of ASD (1-3). The current literature evaluating the effects of treating ASD with Memantine suggest positive preliminary outcomes without serious adverse events reported (1-3). However, the literature primarily evaluates the treatment effect in child and adolescent populations (1-4). There is a lack of research evaluating the treatment of ASD with Memantine in adult populations. Here we present a case of a female diagnosed with severe ASD treated with Memantine.
26-year-old female with no known medical history who presented to the psychiatric clinic for persistent anxiety with uncontrolled trichomania and difficulty in social interactions. She had no previous psychiatric treatment, no prior hospitalizations, and no medication trials. She described chronic interpersonal difficulty with more recent distress related to interactions at her work place. Family history was significant for mother diagnosed with bipolar disorder. Social history noted pervasive difficulty creating and maintaining friendships in childhood, currently living alone, and pursuing an advanced degree in engineering. While in outpatient treatment, she was diagnosed with severe ASD by an outside hospital and initiated on Memantine 5mg BID, which was then titrated to 10mg BID without side effects. Six months after initiation of Memantine, the patient joined an intramural sports team; engaged in more in social outings; and demonstrated improved social interactions in home, school, and professional settings, though she continued to endorse anxiety with some hair pulling.
Memantine is Federal Drug Administration (FDA) approved for treatment of severe Alzheimer’s Disease, and has been trialed as a potential treatment in psychiatric disorders including obsessive compulsive disorder, bipolar disorder and attention-deficit/hyperactivity disorder (ADHD) (4). To date there has only been one prospective 12-week open label trial (n=17) evaluating the effects of Memantine to treat ASD in adults (4). Similar to our case, the prospective trial documented improvement in measures of autism severity, anxiety and ADHD symptoms with no serious adverse events reported (4). In conclusion more research is needed to fully elucidate the efficacy and safety of Memantine in treating ASD in the adult population.