Tackling Negative Symptoms of Schizophrenia with Memantine

Abstract

We present a case of a 52-year-old male patient suffering from chronic schizophrenia stabilized on risperidone long-acting injection (37,5 mg/2 weeks) and biperiden 4 mg/day. Residual symptoms are affective flattening, alogia, avolition, and asociality. Memantine 10 mg/day was added. After 1.5 months, the patient spontaneously referred to “feel better being in company of my relatives.” The following scales have been completed: the Scale for the Assessment of Negative Symptoms (96), the Scale for the Assessment of Positive Symptoms (3), the Mini Mental Scale Examination (26), and the Calgary Depression for Schizophrenia Scale (2). Memantine was increased to 20 mg/day and biperiden was decreased to 2 mg/day. Two months later, apathy and asociality considerably improved and affective flattening, alogia, and attention slightly got better (SANS 76, SAPS 1, MMSE 26, and CDSS 1). After two more months, the improvement continued in the same domains (SANS: 70, SAPS: 1 MMSE: 27, and CDSS: 1). Positive symptoms remained in full remission. It has been hypothesized that one of the causes of schizophrenia is glutamate excitotoxicity. Memantine, a glutamate receptor antagonist, could possibly ameliorate schizophrenia symptoms, the negative ones among them, used as add-on therapy to atypical antipsychotics. Memantine could be of potential help in schizophrenia patients with severe residual negative symptoms.

Potential Role of Antipsychotic-Galantamine-Memantine Combination in the Treatment of Positive, Cognitive, and Negative Symptoms of Schizophrenia

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Single-Dose Memantine Improves Cortical Oscillatory Response Dynamics in Patients with Schizophrenia

“…A chart-based retrospective case series found improved positive and/or negative symptoms as well as cognitive and/or functional domains in 17 out of 26 SZ patients when MEM was added to an antipsychotic (John et al, 2014); in several patients, antipsychotic dose requirements also declined with MEM. Many case reports describe symptom reduction and function gains after MEM (5-20 mg/d) in SZ patients; in some, symptoms returned when MEM was stopped and resolved after MEM was restarted (Zdanys and Tampi, 2008;Matsuda et al, 2013;Paraschakis, 2014).…”

Neurodevelopmental Animal Models Reveal the Convergent Role of Neurotransmitter Systems, Inflammation, and Oxidative Stress as Biomarkers of Schizophrenia: Implications for Novel Drug Development

“…However, a recent case report indicated that another NMDAR antagonist, memantine significantly improved the negative symptoms of schizophrenia when used as add-on therapy. 276 Adjunctive memantine together with clozapine also significantly improved not only the negative symptoms but also positive symptoms in refractory schizophrenia patients. 277 The authors argue that this improvement could be related to memantine's NMDAR antagonistic mechanisms; preventing a toxic influx of Ca 2+ into neuronal cells and as such abrogating oxidative stress (see fig.…”