Eruptive nevi associated with medications (ENAMs) refers to the sudden eruption of nevi temporally associated with medication use. Numerous medications have been linked to ENAMs. Azathioprine and 6-mercaptopurine are the most common culprits. Other medications include corticosteroids, cyclosporine, methotrexate, etanercept, alefacept, infliximab, rituximab, capecitabine, interferon alfa-2b, cyclophosphamide, octreotide, BRAF inhibitors (encorafenib, vemurafenib), sorafenib, sunitinib, erlotinib, regorafenib, Melanotan, and corticotrophin.

ENAMs are more common in individuals with lighter skin phototypes and in those who received renal transplantation or chemotherapy for a hematologic malignancy. There is no sex predilection. The risk for malignant transformation of these nevi is unclear. Concurrent transformation of preexisting nevi into dysplastic nevi has been reported.