PD-1 (programmed cell death-1) inhibitors, used to treat metastatic melanoma and other malignancies, are associated with development of immune-related adverse events in the skin. Such reactions include morbilliform eruptions, vitiligo, alopecia areata and bullous pemphigoid. In this report, we describe a patient who developed a lupus-like cutaneous reaction in the setting of pembrolizumab therapy for metastatic melanoma, adding to the spectrum of reactions which may be observed in association with PD-1 inhibitor therapy. showed a slight increase in mucinous ground substance. These features were interpreted as a lupus-like medication reaction. Based on these findings, pembrolizumab continued to be withheld in the patient. Within 1 month, the rash completely resolved without use of