Original Article

The Effect of Memantine Versus Folic Acid on Cognitive Impairment in Patients with Schizophrenia: A Randomized Clinical Trial


Objective: Schizophrenia, as one of the most severe psychiatric diseases, has a chronic and debilitating process. The majority of patients with schizophrenia do not respond adequately to treatment with common antipsychotic drugs. Therapeutic problems induced by drug side effects as well as undesired results are major challenging issues regarding this disease. This study aimed at evaluating the effect of memantine supplementation on the improvement of cognitive symptoms in patients with schizophrenia.

Method: The present clinical trial was performed on 50 patients with acute schizophrenia who were admitted to Kargarnejad Psychiatric Hospital in Kashan in 2022 and who were diagnosed as schizophrenia cases at least three months ago. Patients were randomly divided into either the intervention group (n = 25) or the placebo group (n = 25). The intervention group received 5 mg of memantine per day for three months. The dose of memantine in this group was increased to the maximum of 20 mg per day. The placebo group received 1 mg of folic acid per day for three months. Moreover, an identical routine schizophrenia therapeutic regimen was administered to all patients. The effectiveness of memantine was evaluated using the Wechsler Adult Intelligence Scale (WAIS-III), which assessed cognitive ability in older adults over a 12-week follow-up period.

Results: The WAIS-III score in the 12th week of the study was significantly different between the placebo and intervention groups (P = 0.004), such that the score of the memantine group was higher than that of the placebo group. No significant difference was observed between the two groups in terms of drug side effects.

Conclusion: Memantine can be supplemented in the treatment of schizophrenia so as to improve the cognitive symptoms of this disorder. However, subsequent studies involving larger sample sizes and different doses seem to be necessary to provide more accurate results in this respect.

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IssueVol 18 No 3 (2023) QRcode
SectionOriginal Article(s)
DOI https://doi.org/10.18502/ijps.v18i3.13002
Cognitive Symptoms Folic Acid Memantine Schizophrenia

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How to Cite
Hosseini SA, Sepehrmanesh Z, Gilasi H, Ghoraishi‬FS. The Effect of Memantine Versus Folic Acid on Cognitive Impairment in Patients with Schizophrenia: A Randomized Clinical Trial. Iran J Psychiatry. 2023;18(3):258-265.