Highlights
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Antipsychotics have been helpful in improving negative symptoms of schizophrenia
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Understanding the role of neurotransmitters in the pathogenesis of schizophrenia has led to the development of new drugs
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Memantine can significantly improve negative and cognitive symptoms among patients with schizophrenia
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Adjunct treatment with NMDA receptor antagonists can be considered as a useful addition to standard care in the future
Abstract
The “glutamate hypothesis of schizophrenia” has changed attitudes in the development of new medications. This study aimed to evaluate the effects of 20 mg of memantine per day (as a NMDA receptor antagonist) added to risperidone among male patients with schizophrenia. In a randomized placebo-controlled, double-blind clinical trial, 46 adult male patients with schizophrenia were evaluated in both intervention and control groups at weeks 0, 6 and 12. The positive and negative symptoms scale and the mini mental status examination were used to assess positive, negative and cognitive symptoms and general psychopathology. The mean age of the patients was 44.8 for the intervention group and 45.3 for the control group, and the mean times since diagnosis were 23.5 and 25.7 years in the intervention and the control group, respectively. Positive and general psychopathologic symptoms showed no significant differences between the two groups at baseline or after treatment; while negative symptoms improved significantly in the intervention group at week 12. Cognitive function was also significantly improved in the intervention group at weeks 6 and 12. Memantine is supported as an effective adjunct treatment to improve negative and cognitive symptoms in patients with schizophrenia.
Keywords
Memantine; Positive and negative symptoms; Cognitive function
http://www.sciencedirect.com/science/article/pii/S0165178116303584