The role of serotonin (5-hydroxytryptamine) in alcohol-induced aggress
ive behaviour is discussed. Considerable evidence exists in support of
an association between aggression and serotonin deficiency and betwee
n aggression and alcohol consumption, and it is also known that alcoho
l consumption exerts major effects on serotonin metabolism. These link
s are synthesized into the serotonin deficiency hypothesis of alcohol-
induced aggressive behaviour, which postulates that individuals suscep
tible to aggression after alcohol consumption exhibit a marked depleti
on of their brain serotonin rendering them prone to aggression in resp
onse to environmental or psychological stimuli or situations. This hyp
othesis has already received support from experimental studies in non-
aggressive subjects, but remains to be examined in those known to be a
ggressive after alcohol consumption.