<h4>Purpose</h4>We present a case of rapid improvement in symptoms of thyroid eye disease and amelioration of worsening peripheral edema and acropathy with infusion of teprotumumab, a monoclonal antibody targeting the insulin-like growth factor-1 receptor.<h4>Observations</h4>A 66 year old female with history of Hashimoto thyroiditis developed progressive thyroid eye disease (TED), peripheral edema, and acropathy attributable to acute Graves disease. This evidence concerns the gene IGF1R and Hashimoto thyroiditis.