Biologics such as infliximab account for a growing multibillion-dollar industry, treating a myriad of inflammatory conditions ranging from psoriasis to inflammatory bowel disease. As patents for these medications expire, a growing market is surfacing to derive highly similar but more affordable therapies, known as biosimilars (McKinnon and Ward, 2016). Because the approval process of biosimilars does not require the same extensive clinical trial phases as the originators, we highlight that informational gaps exist on the postmarking side effects of biosimilars (Yamauchi et al., 2018). The following case presents an example of a new-onset rash in the setting of initiating biosimilar infliximab-dyyb treatment.