The article describes the case of a 41-year-old male who presented with a painful, erythematous, erosive, and scaly rash. Based on patient's history and physical examination findings, the patient had pellagra. Pellagra is a rare condition that is characterized by diarrhea, dermatitis, and dementia. It occurs in the late stage of severe niacin deficiency and can affect the gastrointestinal tract, nervous system, and skin.