Certain anti-inflammatory drugs exert beneficial effects in schizophrenia patients

Several anti-inflammatory drugs, including aspirin, oestrogens, minocycline and N-acetylcysteine (NAC), appear to help mitigate symptom severity in patients with schizophrenia, according to a systematic review and meta-analysis.

Researchers searched multiple online databases for randomized controlled trials that explored concomitant use of anti-inflammatory agents in patients with a schizophrenia spectrum disorder (schizophrenia, schizophreniform disorder or schizoaffective disorder). None of the patients had schizotypal and schizoid personality disorder.

The meta-analysis included 56 studies reporting the effect of the following medications on symptom severity: aspirin, bexarotene, celecoxib, davunetide, dextromethorphan, oestrogens, fatty acids, melatonin, minocycline, NAC, pioglitazone, piracetam, pregnenolone, statins, varenicline and withania somnifera extract.

Pooled data revealed that some medications exerted significant beneficial effects on symptom severity, specifically aspirin (n=270; mean weighted effect size [ES], 0.30, 95 percent CI, 0.06–0.54), oestrogens (n=723; ES, 0.78, 0.36–1.19), minocycline (n=946; ES, 0.40, 0.11–0.68) and NAC (n=442; ES, 1.00, 0.60–1.41). In subgroup analysis, these drugs yielded greater positive effects in patients with first-episode psychosis or early-phase schizophrenia.

There were no beneficial effects observed with bexarotene, celecoxib, davunetide, dextromethorphan, fatty acids, pregnenolone, statins and varenicline.

Taken together, the present data support the immune hypothesis in schizophrenia, which suggests a possible treatment for patients in which the underlying pathophysiology is related to a subtle increase in the activation of microglia, according to the researchers. Despite the evidence, further studies are still needed.