Development of periungual pyogenic granulomas (pPGs) has been associated with several systemic treatments, including retinoids, taxanes, epidermal growth factor receptor inhibitors, and vascular endothelial growth factor inhibitors. We present the case of an 8-year-old girl with a personal history of acute myelomonocytic leukemia treated with a haploidentical hematopoietic stem cell transplant who developed pPGs 2 months after starting ravulizumab. Ravulizumab is a monoclonal antibody directed against C5 protein. No previous reports of pPGs development have been described with ravulizumab.