Ideas about serotonin in OCD
The medications that work to improve OCD symptoms all act on a
brain chemical called serotonin. This is one of the brain's neurotransmitters,
and is one of the ways that brain cells communicate with each other.
It may be that people who have OCD have differences in the way their
brains produce or handle serotonin; these are likely to be very
There have been research studies trying to work out whether people
with OCD really do have differences in their serotonin levels, and
so far there are no definite conclusions. This may be because the
brain is so complicated, and so many different chemicals act together
to influence brain functions such as thinking, feeling, behaving
etc. It is impossible to measure brain chemistry directly, so researchers
have to look at serotonin levels in other parts of the body, such
as the blood, and subtle brain differences may not be detected.
For a detailed review of serotonin in OCD see:
Gross R, Sasson Y, Chopra M, Zohar J: Biological models of obsessive
compulsive disorder: the serotonin hypothesis. In: Swinson R, ed.
Obsessive compulsive disorder: theory, research and treatment. New
York: The Guilford Press, 1998.