Fever

Definition

• Rectal, Ear or Temporal Artery (TA) temperature: 100.4 F (38.0 C) or higher
• Pacifier or Oral temperature: 100 F (37.8 C) or higher
• Axillary (armpit) temperature: 99 F (37.2 C) or higher
• Limitation: Ear (Tympanic) not reliable in less than 6 months of age.
• Temporal artery and skin infrared temperatures may be reliable in young infants (new research).
• Use this guideline if fever is your child's only symptom

Causes

• Main cause: colds and other viral infections
• Fever may be the only symptom for the first 24 hours (i.e., viral fevers). The onset of symptoms (runny nose, cough, diarrhea, etc.) are often delayed. In the case of Roseola, fever may be the only symptom for 2 or 3 days.
• The cause of the fever usually can't be determined until other symptoms develop. That may take 24 hours.
• Bacterial infections (e.g., Strep throat or urinary tract infections) also cause fever
• Teething does not cause fever

Normal variation of temperature

• Rectal: A reading of 98.6 F (37 C) is just the average rectal temperature. It normally can change from 96.8 F (36 C) in the morning to a high of 100.3 F (37.9 C) in the late afternoon.
• Oral: A reading of 97.6 F (36.5 C) is just the average oral temperature. It normally can change from a low of 95.8 F (35.5 C) in the morning to a high of 99.4 F (37.5 C) in the late afternoon.

Return to school

Your child can return to day care or school after the fever is gone and your child feels well enough to participate in normal activities.

When to Call Your Doctor for Fever

• Not moving or very weak
• Unresponsive or difficult to awaken
• Difficulty breathing with bluish lips
• Purple or blood-colored spots or dots on skin

Call your doctor now (night or day) if

• Your child looks or acts very sick
• Not alert when awake
• Any difficulty breathing
• Great difficulty swallowing fluids or saliva
• Child is confused (delirious) or has stiff neck or bulging soft spot
• Had a seizure with the fever
• Age under 12 weeks with fever above 100.4° F (38.0° C) rectally (Caution: Do not give your baby any fever medicine before being seen)
• Fever AND >105 F (40.6 C) by any route or axillary >104 F (40 C). (EXCEPTION: age >1 year, fever down and child comfortable. If recurs, see now.)
• Very irritable (e.g., inconsolable crying or cries when touched or moved)
• Won't move an arm or leg normally
• Signs of dehydration (very dry mouth, no urine in more than 8 hours, etc.)
• Burning or pain with urination
• Chronic disease (e.g., sickle cell disease) or medication (e.g., chemotherapy) that causes decreased immunity

Call your doctor within 24 hours (between 9 a.m. and 4 p.m.) if

• You think your child needs to be seen
• Age 3-6 months with fever
• Age 6-24 months with fever present over 24 hours but no other symptoms (e.g., no cold, cough, diarrhea, etc.)
• Fever repeatedly above 104° F (40° C) despite fever medicine
• Fever present for more than 3 days

Call your doctor during weekday office hours if

• You have other questions or concerns

Parent care at home if

• Fever with no other symptoms AND you don't think your child needs to be seen

Home Care Advice for Fever

1. Reassurance: Presence of a fever means your child has an infection, usually caused by a virus. Most fevers are good for sick children and help the body fight infection. Use the following definitions to help put your child's level of fever into perspective:
   • 100°-102°F (37.8° - 39°C) Low grade fevers: beneficial, desirable range
   • 102°-104°F (39 - 40°C) Mild fever: still beneficial
   • Over 104°F (40°C) Moderate fever: causes discomfort, but harmless
   • Over 105°F (40.6°C) High fever: higher risk of bacterial infections
   • Over 106°F (41.1°C) Very high fever: important to bring it down
   • Over 108°F (42.3°C) Dangerous fever: fever itself can harm brain
2. Treatment for All Fevers: Extra Fluids and Less Clothing
   • Give cold fluids orally in unlimited amounts (reason: good hydration replaces sweat and improves heat loss via skin).
   • Dress in 1 layer of light weight clothing and sleep with 1 light blanket (avoid bundling). (Caution: overheated infants can't undress themselves.)
   • For fevers 100°-102° F (37.8° - 39°C), this is the only treatment needed (fever medicines are unnecessary).
3. Fever Medication:
   • Fevers only need to be treated with medicine if they cause discomfort. That usually means fevers above 102°F (39°C).
   • Give acetaminophen (e.g., Tylenol) or ibuprofen (e.g., Advil). See the dosage charts.
   • The goal of fever therapy is to bring the temperature down to a comfortable level. Remember, the fever medicine usually lowers the fever by 2° to 3° F (1 - 1.5° C).
   • Avoid aspirin (Reason: risk of Reye's syndrome, a rare but serious brain disease)
   • Avoid alternating acetaminophen and ibuprofen (Reason: unnecessary and risk of overdosage)
4. Sponging:
   • Note: Sponging is optional for high fevers, not required.
   • Indication: May sponge for (1) fever above 104° F (40° C) AND (2) doesn't come down with acetaminophen (e.g., Tylenol) or ibuprofen (always give fever medicine first).
   • How to sponge: Use lukewarm water (85 - 90° F) (29.4 - 32.2° C). Do not use rubbing alcohol. Sponge for 20-30 minutes.
   • If your child shivers or becomes cold, stop sponging or increase the water temperature.
5. Contagiousness: Your child can return to day care or school after the fever is gone and your child feels well enough to participate in normal activities.
6. Expected Course of Fever: Most fevers associated with viral illnesses fluctuate between 101° and 104° F (38.4° and 40° C) and last for 2 or 3 days.
7. Call Your Doctor If:
   • Fever goes above 104° F (40° C) repeatedly
   • Any fever occurs if under 12 weeks old
   • Fever without a cause persists over 24 hours (if age less than 2 years)
   • Fever persists over 3 days (72 hours)
   • Your child becomes worse

And remember, contact your doctor if your child develops any of the "When to Call Your Doctor" symptoms.

References

1. AAP Committee on Quality Improvement: Subcommittee on Urinary Tract Infection. Practice parameter: The diagnosis, treatment, and evaluation of the initial urinary tract infection in febrile infants and young children. Pediatrics. 1999;103:843-852.
2. Antonyrajah B, Mukundan D. Fever without apparent source on clinical examination. Curr Opin Pediatr. 2008;20(96):102.
3. Avner JR. Acute fever. Pediatr Rev. 2009;30(1):5-12.
4. Baraff LJ. Management of fever without source in infants and children. Pediatr Ann. 2008;37(10):673-679.
5. Birmingham PK, Tobin MJ, Henthorn TK, et al. Twenty-four hour pharmacokinetics of rectal acetaminophen in children: an old drug with new recommendations. Anesthesiology. 1997;87:244-252.
6. Bonadio WA. The history and physical assessments of the febrile infant. Pediatr Clin North Am. 1998;45(1):65-77.
7. Crocetti MT, Serwint JR. Fever: separating fact from fiction. Contemp Pediatr. 2005;22(1):34-42.
8. Finklestein JA, Christiansen CL, Richard Platt. Fever in pediatric primary care: Occurrence, management and outcomes. Pediatrics. 2000;105:260-266.
9. Graneto JW et al. Maternal screening of childhood fever by palpation. Pediatr Emerg Care. 1996;12(3):183-184.
10. Greenes DS and Fleisher GR. Accuracy of a noninvasive temporal artery thermometer for use in infants. Arch Pediatr Adolesc Med. 2001;155:376-381.
11. Ishimine P. Fever without source in children 0 to 36 months of age. Pediatr Clin North Am. 2006;53(2):167-194.
12. Mayoral CE, Marino RV, Rosenfeld W, Greensher J. Alternating antipyretics: Is this an alternative? Pediatrics. 2000;105:1009-1012.
13. McAbee GN, Donn SM, Mendelson RA, et al. Medical diagnoses commonly associated with pediatric malpractice lawsuits in the United States. Pediatrics. 2008;122:e1282-e1286.
14. McCarthy PL. Fever. Pediatr Rev. 1998;19:401-407.
15. Miller AA. Alternating acetaminophen with ibuprofen for fever. Pediatr Ann.2007;36(7):384-388.
16. Newman TB, Bernzweig JA, Takayama JI, Finch SA, Wasserman RC, Pantell RH. Urine testing and urinary tract infections in febrile infants seen in office settings. Arch Pediatr Adolesc Med. 2002;156:44-54.
17. Press S, Quinn BJ. The pacifier thermometer. Arch Pediatr Adolesc Med. 1997;151:551-554.
18. Rideout ME, First LR. Fever: measuring and managing a sizzling symptom. Contemp Pediatr. 2001;18(5):42-50.
19. Roberts KB. Young febrile infants. JAMA. 2004;291(10):1261-1262.
20. Sarrell EM, Wielunsky E, Cohen HA. Antipyretic treatment in young children with fever. Arch Pediatr Adolesc Med. 2006;160:197-202.
21. Scolnik D et al. Comparison of oral versus normal and high-dose rectal acetaminophen in the treatment of febrile children. Pediatrics. 2002;110:553-556.
22. Shann F. Comparison of rectal, axillary and forehead temperatures. Arch Pediatr Adolesc Med. 1996;150: 74-78.
23. Tal Y, Even L, Kugelman A, et al. The clinical significance of rigors in febrile children. Eur J Pediatr. 1997; 156:457-459.
24. Trautner BW, Caviness C, Gerlacher G, et al. Prospective evaluation of the risk of serious bacterial infection in children who present to the emergency department with hyperpyrexia. Pediatrics. 2006;118(1):34-40.

Disclaimer

This information is not intended be a substitute for professional medical advice. It is provided for educational purposes only. You assume full responsibility for how you choose to use this information.

Author and Senior Reviewer: Barton D. Schmitt, M.D.

Last Reviewed: 1/4/2010

Last Revised: 12/11/2009 3:35:33 PM

Copyright 1994-2010 Barton D. Schmitt, M.D.