Fever
- Fever is also the name of an album by Kylie Minogue.
- Fever is also the name of a rock'n'roll song composed by Otis Blackwell
Fever, also known as pyrexia, is a medical symptom which describes an increase in temperature to levels which are above normal (37.8 degrees Celsius). Most fevers are caused by infections and almost all infectious diseases cause fever. When a patient has or is suspecting of having a fever, that person's body temperature is measured using a thermometer.
Fever usually occurs in response to pyrogens (e.g. prostaglandins) which are released from inflammatory cells. These pyrogens act on the hypothalamus (the body's thermostat), resetting it to a higher temperature and in doing so invoking the body's temperature raising mechanisms and raising the body temperature to a level above normal. The body's temperature is maintained at that level until the effects of the pyrogens wear off.
Pyrexia can be classed as low grade (38 to 39 ÃÂðC), moderate (39 to 40 ÃÂðC), or high grade (more than 40 ÃÂðC) depending on how much the body temperature has deviated from normal.
It may be of benefit and is part of the body's response to a disease; however, if the fever goes above 42 ÃÂðC then it may cause significant tissue damage and would most certainly be harmful.
Drugs that reduce fever are known as antipyretics. Common antipyretics are acetaminophen, also called paracetamol, and aspirin.