Abstract
Heatstroke represents the most severe end of the heat illness spectrum, and is increasingly seen in those undergoing exercise or exertion ('exertional heatstroke') and those exposed to high ambient temperatures, for example in heatwaves ('classical heatstroke'). Both forms may be associated with significant thermal injury, leading to organ dysfunction and the need for admission to an intensive care unit. The process may be exacerbated by translocation of bacteria or endotoxin through an intestinal wall rendered more permeable by the hyperthermia. This narrative review highlights the importance of early diagnosis, rapid cooling and effective management of complications. It discusses the incidence, clinical features and treatment of heatstroke, and discusses the possible role of intestinal permeability and advances in follow-up and recovery of this condition. Optimum treatment involves an integrated input from prehospital, emergency department and critical care teams, along with follow-up by rehabilitation teams and, if appropriate, sports or clinical physiologists.