Medical Encyclopedia

 

Medical Encyclopedia

Other encyclopedia topics:  A-Ag  Ah-Ap  Aq-Az  B-Bk  Bl-Bz  C-Cg  Ch-Co  Cp-Cz  D-Di  Dj-Dz  E-Ep  Eq-Ez  F  G  H-Hf  Hg-Hz  I-In  Io-Iz  J  K  L-Ln  Lo-Lz  M-Mf  Mg-Mz  N  O  P-Pl  Pm-Pz  Q  R  S-Sh  Si-Sp  Sq-Sz  T-Tn  To-Tz  U  V  W  X  Y  Z  0-9 

Fever

Contents of this page:

Illustrations

Thermometer temperature
Thermometer temperature
Temperature measurement
Temperature measurement

Alternative Names    Return to top

Elevated temperature; Hyperthermia; Pyrexia

Definition    Return to top

Fever is the temporary increase in the body's temperature, in response to some disease or illness.

A child has a fever when their temperature is at or above one of these levels:

An adult probably has a fever when their temperature is above 99 - 99.5 °F (37.2 - 37.5 °C), depending on what time of the day it is.

See also:

Considerations    Return to top

Normal body temperature may change during any given day. It is usually highest in the evening. Other factors that may affect body temperature are.

Fever is an important part of the body's defense against infection. Many infants and children develop high fevers with minor viral illnesses. While a fever signals to us that a battle might be going on in the body, the fever is fighting for the person, not against.

Most bacteria and viruses that cause infections in people thrive best at 98.6°F. Many infants and children develop high fevers with minor viral illnesses. While a fever signals to us that a battle might be going on in the body, the fever is fighting FOR the person, not against.

Brain damage from a fever generally will not occur unless the fever is over 107.6 °F (42 °C). Untreated fevers caused by infection will seldom go over 105 °F unless the child is overdressed or trapped in a hot place.

Febrile seizures do occur in some children. However, most febrile seizures are over quickly, do not mean your child has epilepsy, and do not cause any permanent harm..

Unexplained fevers that continue for days or weeks are called fevers of undetermined origin (FUO).

Causes    Return to top

Almost any infection can cause a fever. Some common infections are

Children may have a low-grade fever for one or two days after some immunizations.

Teething may cause a slight increase in a child's temperature, but not higher than 100 °F.

Autoimmune or inflammatory disorders may also cause fevers. Some examples are:

The first symptom of a cancer may be a fever. This is especially true of Hodgkin's disease, non-Hodgkin's lymphoma, and leukemia.

Other possible causes of fever include

Home Care    Return to top

A simple cold or other viral infection can sometimes cause a high fever (102 - 104 °F, or 38.9 - 40 °C). This does not usually mean you or your child have a serious problem. Some serious infections may cause no fever or even a very low body temperature, especially in infants.

If the fever is mild and have no other problems, you do not need treatment. Drink fluids and rest.

The illness is probably not serious if your child:

Take steps to lower a fever if you or your child are uncomfortable, vomiting, dried out (dehydrated), or not sleeping well. Remember, the goal is to lower, not eliminate, the fever.

When trying to lower a fever:

Here are some guidelines for taking medicine to lower a fever:

Eating and drinking with a fever

When to Contact a Medical Professional    Return to top

Call a doctor right away if your child:

Call 911 if you or your child has a fever and:

Call your doctor right away if you are an adult and you:

What to Expect at Your Office Visit    Return to top

Your doctor will perform a physical examination, which may include a detailed examination of the skin, eyes, ears, nose, throat, neck, chest, and abdomen to look for the cause of the fever.

Treatment depends on the duration and cause of the fever, and on other accompanying symptoms.

The following diagnostic tests may be performed:

References    Return to top

American College of Emergency Physicians Clinical Policies Subcommittee on Pediatric Fever. Clinical policy for children younger than three years presenting to the emergency department with fever. Ann Emerg Med. 2003;42(4):530-545.

Legget J. Approach to fever or suspected infection in the normal host. Goldman L, Ausiello D, eds. Cecil Medicine, 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007: chap 302.

Update Date: 4/17/2009

Updated by: A.D.A.M. Editorial Team: David Zieve, MD, MHA, Greg Juhn, MTPW, David R. Eltz. Previously reviewed by Rachel A. Lewis, MD, FAAP, Columbia Pediatric Faculty Practice, New York, NY. Review provided by VeriMed Healthcare Network (2/27/2008).

A.D.A.M. Logo

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 1997-2009, A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.