Compared to bupropion, hydroxybupropion is similar in its potency as a norepinephrine reuptake inhibitor (IC50 = 1.7 μM), but is substantially weaker as a dopamine reuptake inhibitor (IC50 = >10 μM).[3] Like bupropion, hydroxybupropion is also a non-competitive antagonist of nACh receptors, such as α4β2 and α3β4, but is even more potent in comparison.[2][3][4][5][6]