In one study, nortriptyline had the highest affinity for the dopamine transporter among the TCAs (KD = 1,140 nM) besides amineptine (a norepinephrine–dopamine reuptake inhibitor), although its affinity for this transporter was still 261- and 63-fold lower than for the norepinephrine and serotonin transporters (KD = 4.37 and 18 nM, respectively).
