EVALUATING THE EFFICACY OF RILUZOLE ADD-ON THERAPY ON TREATMENT SYMPTOMS OF PATIENTS WITH CONTINUOUS SCHIZOPHRENIA

This study was aimed to evaluate the efficacy of riluzole (a glutamate release inhibitor) add-on therapy in the treatment of negative symptoms of patients with chronic schizophrenia. This randomized, double-blind, and placebo-controlled study was conducted on thirty patients with continues schizophrenia (DSM-IV-TR) that were randomized considering either riluzole (100 mg daily) or placebo in addition to risperidone 6 mg/day for eight weeks. The patients were assessed using positive and negative syndrome scale (PANSS) and extrapyramidal symptom rating scale (ESRS) at baseline, week 4 and 8. Hamilton depression rating scale (HDRS) was used to assess depression at baseline and week 8. Thirty patients completed the trial. Riluzole group showed a significantly greater improvement on negative subscale than the placebo group at endpoint (P<0.001). The same effect was observed for the total score (P<0.001) and general psychopathology score (P=0.001). However the placebo and riluzole groups did not differ in their reduction of positive symptoms scores. HDRS and ESRS scores and their changes did not differ between the two groups. Frequency of other side effects was similar between the two groups. Riluzole add-on can reduce the primary negative symptoms of patients with schizophrenia.