Neuropsychiatric manifestations of Systemic Lupus Erythematosus (NPSLE) are both common and
an important source of morbidity. Of the case definitions for NPSLE syndromes that have
recently been developed, cognitive dysfunction appears to be the most prevalent. A novel
mechanism is that a subset of SLE patients with cognitive dysfunction have antibodies in the
NR2 glutamate receptor. We propose, in a double -blind placebo-controlled trial, to determine
whether SLE patients, with or without the NR2 glutamate receptor antibody, have significant
improvement using memantine, an inhibitor of the NMDA receptor.