Fever

Fever, an elevation above normal body temperature, is a frequent symptom of many infections [1]. It results from the release of endogenous pyrogens such as prostaglandins and cytokines, which act on the anterior hypothalamus to increase the body’s temperature ‘set point’ [1]. Antipyretics like paracetamol (acetaminophen) appear to work by antagonizing prostaglandins, and aresomeof the most commonlyused drugs in clinical practice [1]. Fever is usually regarded as a ‘noxious’ state that should be reversed in order to reduce morbidity, including convulsions and mortality [2]. This view is, surprisingly, not based on any experimental data [2] but rather a fear of any harmful effects [3]. Although antipyretics may ease discomfort during illness, this is likely due to the analgesic effects of most antipyretics rather than any reduction in temperature. Few clinical trials provide evidence for the use of antipyretics. On the contrary, fever appears to be an evolved defence mechanism [2, 4], the suppression of which appears to have negative consequences [1, 5]. Evolutionary perspectives