Molecular weight: 176
Formula: C10H12N2O
Serotonin is a molecule which is essentially a neurotransmitter. It is related to "happiness" and "well-being". It exists mainly in the enteric nervous system (most of it) and the central nervous systems. Medications that reduce the reuptake of serotonin are used for he treatment of depression. Serotonin acts in the 5HT receptors.