Infant botulism is caused by the ingestion of Clostridium botulinum spores and leads to a life-threatening descending motor weakness and flaccid paralysis in infant children. This disease presents with symptoms such as constipation, weakness, and hypotonia and can lead to respiratory failure. Botulism immune globulin (BIG) was created to treat this deadly disease and functions by neutralizing all systemically circulating botulism toxins. It is indicated in children with clinically diagnosed infant botulism, before diagnostic confirmation, and has been shown to lead to a significant reduction in intensive care unit and hospital stay for these patients. This review article discusses the epidemiology, clinical presentation, history of BIG, and indications for administration of BIG.