Thyroid eye disease (TED) presents with varying degrees of proptosis, eyelid retraction, diplopia, congestion, and infrequently, compressive optic neuropathy (CON). The US Food and Drug Administration (FDA) recently approved teprotumumab for the treatment of TED. The effectiveness of teprotumumab for CON is currently unclear. In this study, we report the clinical course of a patient with TED and early CON who improved after a single teprotumumab infusion, with sustained improvement at 25 weeks following the initial dose.