M. J. Schwarz. Psychiatric Hospital, LMU Muni, Munich, Germany

B. Speraer-Unterweger. Psychiatric Hospital, Universi, Innsbruck, Austria

M. Riedel. Psychiatric Hospital, LMU Muni, Munich, Germany

P. J. Egger. Greenford, United Kingdom

N. Müller. Ludwig Maximilian University Psychiatric Hospital, Munich, Germany

Cyclooxygenase-2 (COX-2) - constitutively expressed in the CNS - is suggested to have an important functional role in the CNS. COX-2 interacts with neurotransmitters such as acetylcholine, serotonin, and glutamate, but is also involved in the regulation of immune system and in inflammation in the central nervous system (CNS) via effects of prostaglandins, in particular prostaglandin E2. The relationship between the tryptophan/serotonin metabolism and the differential effects of COX-1 and COX-2 will be discussed by G. Engbert, Stockholm. While Markus Schwarz Miinchen, Germany, will present data showing that inflammation, cytokines and PGE2 plays a role in the etiopathology of schizophrenia, Michael Riedel Miinchen, Germany, will focus on the effects of COX-2 inhibitors on neurotransmitters, which are involved in schizophrenic psychopathology. Recently, a role for the new generation of selective COX-2 inhibitors in the treatment of psychiatric disorders is discussed. Peter Egger, Greenford, UK will present epidemiological data of 716 schizophrenic patients who had a prescription of a selective COX-2 inhibitor (celecoxib or rofecoxib). Compared to schizophrenics without a COX-2 inhibitor, the COX-2 inhibitor users had a 36% reduced risk for a schizophrenic exacerbation independent from antipsychotic medication. Results of two double-blind, randomized studies, altogether with 90 schizophrenic patients will be presented by Norbert Muller, Miinchen, Germany. The results show, that celecoxib has significant beneficial effects not only at the PANSS total scale, but also regarding the general psychopathology and on the schizophrenic negative symptoms. The fact that the therapeutic effect depends from the duration of the disease fits with the inflammation hypothesis. In depression, however, signs of inflammation have been described since many years. Clinical improvement of a depressive syndrome has been observed in patients, which have been treated rofecoxib due to other indications. First data of the use of COX-2 inhibitors in affective disorders will be presented.