Abstract
BACKGROUND: For over 130 years, scientists have been suggesting that infection and inflammation may play a role in psychosis and other psychiatric disorders. First attempts to treat psychosis by immune-modulating therapies were made early in the last century; however, after the development of antipsychotics in the 1950s, scientific interest shifted away from immunological aspects of psychiatric disorders to the involvement of catecholamines, in particular dopamine, in psychosis. SUMMARY: Antipsychotic treatment was not as successful as expected, so the 1990s saw renewed interest in inflammation and psychoneuroimmunological research in schizophrenia and beyond. In parallel, advances in immunological research methods allowed immunological and inflammatory mechanisms to be studied in more detail. KEY MESSAGES: Clinical studies and meta-analyses have demonstrated positive effects of anti-inflammatory treatment in certain patients with psychiatric disorders. More research is needed to elucidate exactly how immunological mechanisms result in disease pathophysiology, with the aim to improve anti-inflammatory and personalized treatments.