鈥� This article reviews the function of prostaglandins (PGs) in the nervous system and discusses the possible alterations in PG metabolism as relating to mental illness. The PGs are a unique group of cyclic fatty acids whose immediate precursors are thought to function postsynaptically by inhibition or facilitation of neurotransmission through cyclase inhibition or activation, and by means of a negative feedback loop to inhibit further release of neurotransmitter from the presynaptic nerve. A review of PGs in psychiatric conditions is presented as well as a discussion of the interaction of psychoactive drugs with the PGs. The concluding section of this review discusses possible future strategies to provide insight into PG physiology as it relates to synaptic transmission in normal and pathological conditions in man.