# Paroxetine Mesylate

National Cancer Institute

## Source

National Cancer Institute. *Paroxetine Mesylate*. NCI Thesaurus. Code C47653.

The mesylate salt form of paroxetine, a phenylpiperidine derivative and a selective serotonin reuptake inhibitor (SSRI) with antidepressant and anxiolytic properties. Paroxetine binds to the pre-synaptic serotonin transporter complex resulting in negative allosteric modulation of the complex, thereby blocking reuptake of serotonin by the pre-synaptic transporter. Inhibition of serotonin recycling enhances serotonergic function through serotonin accumulation in the synaptic cleft, which resulting in long-term desensitization and downregulation of 5HT1 (serotonin) receptors and leading to symptomatic relief of depressive illness.