Erythema Nodosum Leprosum (ENL) is a rare immune-mediated complication of leprosy, characterized by painful nodules and fever, and can lead to anemia and leucocytosis. A 19 y old male with a history of non-adherence to 12 adult multi-bacillary multi-drug therapy packs for leprosy presented with a 15 d complaint of fever and aggravated painful, raised, red skin lesions over two y. Laboratory findings showed neutrophilia, thrombocytosis, microcytic anemia, and traces of blood and ketones in the urine. Acid-fast bacilli with a grade of 1+ were observed in Ziel-Neelson-stained smears, confirming the diagnosis. The patient received systemic Dexamethasone, the standard treatment for Erythema Nodosum Leprosum, and resumed leprosy treatment. Symptomatic care was given, and the patient was discharged. This case highlights the importance of early detection, efficient monitoring, and adherence to therapy to reduce ENL-related morbidity and mortality. The study emphasizes that a regular watch should be kept on leprosy patients to ensure early intervention and prevention of complications.