Nonsteroidal anti-inflammatory drugs and 5-HT₃ serotonin receptor antagonists as innovative antipsychotic augmentation treatments for schizophrenia.

Antipsychotic treatment is the mainstay in the management of schizophrenia. However, despite optimum use of antipsychotic drugs, many schizophrenia patients continue to exhibit residual positive, negative, cognitive, and other symptoms. Various antipsychotic augmentation strategies have been studied using non-antipsychotic augmenting agents; 2 innovative classes of drugs examined have been nonsteroidal anti-inflammatory drugs (NSAIDs) and 5-HT₃ serotonin receptor antagonists. Meta-analysis of the NSAID studies in schizophrenia patients with positive symptoms (8 randomized controlled trials [RCTs], pooled N = 774) shows that NSAID augmentation is associated with a significant decrease in positive symptom ratings (standardized mean difference [SMD] = 0.19), with no significant change in negative or total symptom ratings. Meta-analysis of the 5-HT₃ antagonist studies in stable schizophrenia patients (6 RCTs, pooled N = 311) shows that 5-HT₃ antagonist augmentation is associated with significant reduction in negative symptom (SMD = 1.10), general psychopathology (SMD = 0.70), and total symptom (SMD = 1.03) ratings without reduction in positive symptom ratings. Neither NSAID nor 5-HT₃ antagonist augmentation increases the dropout rate. Whereas the benefits with NSAID augmentation are, perhaps, too small to be clinically meaningful, antipsychotic augmentation with 5-HT₃ antagonists may be a possible strategy to reduce persistent negative symptoms in schizophrenia. Both fields of inquiry require further investigation.