Erythema ab igne (EAI) is a persistent, chronic skin condition resulting from prolonged exposure to infrared radiation, experienced as heat. Once associated with traditional warming sources like wood burning stoves or open fires, modern, infrared exposure originates also from newer sources like laptops and heating pads and may be creating a rebound of EAI. The epidemiology may be different too, with younger patients than previously seen. Localized EAI over an area of pain in the abdomen or lower back can be a sign of an underlying disorder, including cancer. Prognosis of EAI is good, with removal of the heat source resulting in complete remission. In chronic cases in which premalignant cutaneous dysplasia has resulted, additional treatments may be necessary including topical retinoids, 5-fluorouracil cream, and laser treatments. Rarely, cancers such as squamous cell carcinoma, Merkel cell carcinoma, and cutaneous marginal zone B cell lymphoma have been associated with longstanding EAI.