Controlled trial of hydroxychloroquine in schizophrenia.

Hydroxychloroquine is widely employed for the treatment of rheumatological diseases. A preliminary pilot study suggested that hydroxychloroquine may be a useful adjunct for the treatment of schizophrenia, which has been associated with abnormalities in several proinflammatory cytokines. Sixty-one patients were randomized to receive 200 mg/ day hydroxychloroquine or placebo in addition to standard typical antipsychotic treatment. After 8 weeks of double-blind treatment, there was no significant interaction between treatment status and length of treatment for positive, negative, or general symptoms according to the Positive and Negative Syndrome Scale, despite a hydroxychloroquine-associated decrease in serum interferon-gamma levels. After completion of the 8-week study, all participants were offered open treatment with hydroxychloroquine for an additional 12 weeks. Open treatment produced no further improvement in Positive and Negative Syndrome Scale scores at weeks 12, 16, and 20. Further study will be required to determine the role of anti-inflammatory treatments for schizophrenia.