Beyond specificity: effects of serotonin and serotonergic treatments on psychobiological dysfunction.

Serotonin is a ubiquitous neurotransmitter with widespread projections that provide for the involvement of serotonin in the regulation of many biological and psychological functions. A variety of serotonin receptor subtypes exist that mediate overlapping psychobiological functions and that are targets for a new generation of medications. Although these new generation medications appear to possess great biochemical specificity, their actions extend to many psychiatric disorders, reflecting the many interactions of serotonergic subsystems.