Introduction: Bupropion is used to help people stop smoking. This drug can cause visual alterations but, up to now, its use was not associated with anisocoria.
Case report: A 40 year-old woman with a personal history of migraines, presented with monocular mydriasis during treatment with bupropion. Both pupils dilated equally after a 5% cocaine test, and constricted equally after a 0.025% Pilocarpine test. The anisocoria disappeared after the treatment with bupropion was withdrawn.
Discussion: Bupropion inhibits neural uptake of norepinephrine and dopamine. Patients with migraine could have a minor unilateral sympathetic pupillary deficit. This deficit could cause hypersensitivity in the oculosympathetic pathway that could be stimulated with bupropion treatment. This feature could explain the mydriasis in our patient. Another explanation could be that bupropion could unmask a physiological anisocoria.