 It also binds to the allosteric site of the serotonin transporter, similarly, but less potently, than escitalopram.Paroxetine also inhibits the reuptake of norepinephrine to a lesser extent (<50 nmol/L).Based on evidence from four weeks of administration in rats, the equivalent of 20 mg paroxetine taken once daily occupies approximately 88% of serotonin transporters in the prefrontal cortex.