Top definition
A neurotransmitter believed to regulate mood. SSRI's inhibit the reuptake of serotonin in the brain (leading there to be more serotonin left as a result), hopefully improving the mood.

Personally, a good blast on the Codeine cheers me up more than any SSRI.
Perhaps it's my endorphine system rather than my serotoninergic system that is fucked.
A lack of Serotonin is believed to be a cause of depression. It also controls appetite, among other things.

Antidepressants often (through various mechanisms) increase the amount of serotonin in the brain.

MDMA (Ecstacy) causes a massive (cascading) release of serotonin in the brain - responsible for both it's euphoric effects, and the depressive aftereffects (less serotonin remains in the brain, until generated again)
by heterocodeine December 15, 2008
Mug icon

The Urban Dictionary Mug

One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.

Buy the mug