Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impairment in social, behavior and communicative skills. The current therapy for ASD only targets the associated symptoms such as aggression, self-harming acts or temper tantrums but not the core symptoms of social dysfunction. The pathology of ASD is not fully understood. Interestingly, imaging studies in ASD patients have reported abnormal high levels of glutamate in certain brain regions that play an important role in social interaction and communication. Thus, it has been hypothesized that medications attenuating glutamate transmission may be used as treatment for some of the core symptoms of ASD. Memantine, an N-methyl-D-aspartate (NMDA) receptor antagonist, has been approved for the treatment of Alzheimer's disease, and has shown promise in alleviating some of the symptoms of ASD in children. In this review, we will discuss the pathology of ASD, findings from studies that evaluated memantine in ASD patients, the adverse effects of memantine and the potential use of memantine in the treatment of ASD. Finally, we will discuss the role of the pharmacist in managing patients with ASD.