Paroxetine is a phenylpiperidine derivative that potently and selectively inhibits the reuptake of serotonin, blocking the human serotonin transporter with a Ki value of 0.72 nM. It less effectively blocks the human norepinephrine and dopamine transporters (Ki = 440 and 1,900 nM, respectively). Paroxetine also inhibits, at concentrations in excess of 1 μM, nitric oxide synthase activity in the cytosol of hamster brain. Selective serotonin uptake inhibitors, including paroxetine, are used in cases of depression and anxiety disorder.
