Understanding and Preventing Violence, Volume 2: Biobehavioral Influences (1994)
Chapter: Serotonin (5-Hydroxytryptamine)
violent behavior is the use of beta-blockers primarily for their effects on the central nervous system rather than for their autonomic effects. Drugs that block adrenergic beta-receptors also act on certain subtypes of serotonin receptors, and their aggression-reducing effects may be derived from their action on these latter sites. Beta-blockers have not been compared in effectiveness and side effects, particularly during long-term treatment, with other therapeutic agents that reduce aggressive and violent activities.
Clonidine, an adrenergic drug that targets a specific alpha-receptor subtype, has been used with success in managing withdrawal from alcohol, nicotine, and opiate addiction. Evidence from animal and human studies demonstrates that withdrawal states are often associated with irritability and a higher incidence of aggressive and defensive acts.
The application of therapeutic agents with increasing selectivity for adrenergic receptor subtypes to managing and treating patients with violent outbursts represents an important therapeutic alternative to the classic antipsychotics.
Serotonin (5-Hydroxytryptamine)
For the past 30 years, the most intensively studied amine in violent individuals has been serotonin. Evidence from studies ranging from invertebrates to primates highlights marked changes in aspects of serotonin activity in bodily fluids or neural tissue in individuals that have engaged in violent and aggressive behavior on repeated occasions. There is considerable evolutionary variation in the role of serotonin in mediating aggressive or violent behavior across animal species, functionally divergent roles even being represented at the nonhuman primate level. In psychiatric studies, deficits in serotonin synthesis, release, and metabolism have been explored as potential "markers" for certain types of alcoholic and personality disorders with poor impulse control. It is very difficult to extract, from single measures of whole brain serotonin or blood levels, activity information that is specific to past violent behavior, or represents a risk for future propensity, without also considering seasonal and circadian rhythmicity, level of arousal, nutritional status, or past drug history, particularly alcohol abuse. No single type or class of violent activity has emerged as being specifically linked to a "trait" serotonin metabolite level. However, challenges with pharmacologic probes and physiologic or environmental stresses begin to reveal an important profile of serotonin-mediated response patterns.
