Small dose of rituximab for graves orbitopathy: new insights into the mechanism of action.

citing role as increased levels of dopamine have been shown to cause choroidal vasodilation. The time course of effusion development in this case is similar to that with topiramate. This suggests that if bupropion use were causative, one of its major active metabolites, hydroxybupropion or theobupropion (both with half-lives similar to that of topiramate), may be responsible. Both metabolites inhibit dopamine and norepinephrine reuptake; thus, norepinephrine could also have a role. Bilateral effusions have been reported with venlafaxine hydrochloride, a norepinephrine and serotonin reuptake inhibitor. Bupropion is a common medication, and it is unclear why other cases have not been reported. If bupropion use were causative in this case, the absence of other similar reports may reflect underreporting; alternatively, this patient may harbor a rare, private polymorphism that causes bupropion or one of its metabolites to become a particularly potent choroidal vasodilator.