Serotonin Unit Converter

Serotonin, also known as 5-hydroxytryptamine (5-HT), is both a neurotransmitter and a hormone. It is synthesized from the essential amino acid tryptophan and plays a critical role in regulating mood, sleep, appetite, digestion, and many other bodily functions.

Approximately 90–95% of the body's serotonin is produced in the gastrointestinal tract by enterochromaffin cells. The remaining 5–10% is synthesized in the brain's raphe nuclei. Because serotonin cannot cross the blood-brain barrier, these two pools function independently.

Most circulating serotonin is stored in platelets, where it is released during blood clotting. Blood serotonin testing is primarily used to detect carcinoid tumors, which are neuroendocrine tumors that can produce excess serotonin.

Serotonin is produced primarily by enterochromaffin cells in the gastrointestinal tract (about 90–95%) and by serotonergic neurons in the brain's raphe nuclei. It is synthesized from the amino acid tryptophan via the intermediate 5-hydroxytryptophan (5-HTP).