Hyperpyrexia describes an excessive elevation of body temperature above the average normal temperature. It may be caused by the vast majority of agents which precipitate a pyrexia of unknown origin, however, relatively common causes include:
- excessive sun exposure
- bacterial septicaemia
- viral infection e.g. infectious mononucleosis
Rarer examples include the syndrome of malignant hyperpyrexia and thyrotoxic crisis.
Treatment should target the underlying condition before the onset of complications such as heat stroke.