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.
Materials & Methods: 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.
Results: 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.
Conclusions: Riluzole add-on can reduce the primary negative symptoms of patients with
schizophrenia.