- Fever is a powerful yet misunderstood physiological response of the human body.
- A fever indicates that the body’s immune system is functioning the way it is intended.
- Mistrust in the body’s natural processes has led us to fear the occurrence of a simple fever.
If your child has a low fever, do you race to the medicine cabinet and reach for acetominophen (Tylenol) or another antipyretic (fever medicine) to lower your child’s body temperature as soon as possible? Do you call the pediatrician right away? While this is no doubt a natural reaction from parents concerned about their child’s illness, is your child’s fever always a cause for concern and is the rush to lower it the best option?
Most times, a simple fever is an indication that your child’s immune system is fighting a viral or bacterial infection; it is a sign that the body’s defense system is working the way it is intended to work. Fever is greatly misunderstood and perceived as a symptom always to be feared rather than an ally indicating that our bodies have mounted an inflammatory response to fight an infection.
Fever: The Physiology of Body Temperature
Fever is part of a normal, effective immune response and research suggests that immune function actually may be enhanced by fever.1 Fever is a homeostatic process that occurs when the body’s set point is raised above the body’s normal temperature range. Normal body temperature tends to fluctuate on a daily basis ranging from about one degree below to one degree above 98.6 degrees Fahrenheit.2
Depending upon the place on the body at which the measurement is made, body temperature can also vary slightly. While it is believed that rectal (internal) temperature tends to be higher than skin (surface) temperature and that oral and armpit temperatures measure actual body temperature,2 a fluctuating range of temperatures has been found in healthy people.3
Fever can be triggered by several conditions; however, infections usually lead to fever in children.4 Fevers signal an immune system response to gain advantage over microbes that have become pathogenic by preparing the body to create an unfavorable environment against replicating viruses and bacteria that are temperature sensitive.2
This is how it works—Body temperature is regulated by a part of the brain known as the hypothalamus, the body’s thermostat.2 Biochemical substances called pyrogens activate the hypothalamus. Pyrogens travel from areas in the body that are identified by the immune system as a threat to the hypothalamus via the bloodstream.2 Thereafter, the hypothalamus alerts the body to generate and retain heat, which produces a fever.2 5
Consequently, the body responds by constricting blood vessels, increasing muscle tension and releasing hormones such as epinephrine and adrenaline to prevent the release of heat.5 It is this rising internal temperature that causes a person with fever to shiver until the body’s temperature levels off during which the person experiences uncomfortable heat.5 6 When a fever subsides, the body’s internal temperature starts to decline forcing the body to cool off faster, which results in sweating and indicates that the fever is “breaking” and is almost over.5 6
According to the U.S. National Library of Medicine, a child has a fever when the temperature is at or above one of these levels below:7
- 100.4°F (38°C) measured in the bottom (rectally)
- 99.5°F (37.5°C) measured in the mouth (orally)
- 99°F (37.2°C) measured under the arm (axillary)
An adult has a fever when the body temperature is above 99 – 99.5°F (37.2 – 37.5°C), depending on the time of day.7
Lowering Fevers With Over-the-Counter Medications
Fever is part of the body’s healing response to infections and there is growing recognition among more doctors that it makes sense to let a simple fever run its course if a child is not severely distressed.8 In most cases, fever-reducing drugs will only suppress the natural healing mechanisms of the fever and prolong the illness. An article originally published in the Mothering Magazine states that,
It makes sense to us that if fever helps defend against infection, giving fever-reducing medications may make things worse. In addition, some fever medications can have undesirable side effects… Fever medications may actually prolong the illness. This opinion of some practitioners is backed by a few studies. Assuming the response of the body to illness (fever, inflammation, sleepiness) is adaptive, it seems reasonable to assume that interfering with the process may do more harm than good.4
On the safety of fever-reducing medication, an article published in the Archives of Disease in Childhood journal states:
The main problem in assessing the safety of antipyretic drugs is the lack of data. Although systematic reviews have been undertaken, these are reviews of studies that were generally underpowered or insufficiently sensitive to identify toxicity in many cases. At the other end of the scale are case reports and series that suggest a range of toxicities. These include gastrointestinal bleeding, renal injury and secondary infections for ibuprofen; and liver toxicity and asthma for paracetamol. In general, these side effects appear to be rare. More of a concern is likely to be giving too much of these drugs, either because too large a volume is given or because they are given too often. Errors in dosing are not restricted to parents either; data from Scotland suggesting that many prescriptions from general practitioners contain errors.8
Tylenol, which contains acetaminophen, is the most frequently used over-the-counter fever-lowering medication used in the U.S. and around the world. In 2005, about 28 billion doses of Tylenol were used by children and adults in the U.S. The U.S. Food and Drug Administration (FDA) has linked Tylenol to liver damage. In 2007, parents sued Tylenol’s maker, Johnson & Johnson, after their one-year old child died from liver failure after taking infant Tylenol and they received a $5 million jury verdict.9
Traditional Fever Reducing Measures
There are common sense ways to help lower a fever without medicine and make a child feel more comfortable:
- keep room comfortably cool and child dressed lightly
- encourage drinking of fluids, such as water, diluted fruit juices
- sponge baths with lukewarm/slightly cool water10
When is Fever Dangerous?
In most cases, fevers are easily overcome with plenty of rest and fluids that helps the body heal and prevents dehydration. However, a very high fever, especially a prolonged high fever, could be a sign of something that requires immediate medical attention. It may be a sign of an infection too serious for the body to overcome by itself.11 According to Dr. Joseph Mercola, medical attention is warranted for a fever in infants and toddlers when:11
- An infant less than 1 month old has a temperature of greater than 100.4°F
- Infants between the ages of 1 month to 3 months old have a temperature greater than 100.4°F, if they appear ill.
- Children between 3 months and 36 months with a temperature over 102.2°F, if they appear ill.
- For all other age groups, a temperature over 104.5°F.
Some doctors also consider a temperature between 103.F and 104F, especially one that lasts for several days, to be a reason to seek medical attention for children and adults at any age to make sure the person does not have something more serious.12
A sudden high fever that is accompanied by a stiff neck, severe headache, nausea/vomiting, confusion and disorientation, extreme lethargy or seizures can be a sign of meningitis, and requires immediate treatment.13
Sometimes a fever can trigger a seizure (convulsion) in young children, usually between the ages of nine months and five years old. Febrile seizures can run in families and, most of the time, this type of seizure affects toddlers experiencing even a low fever within the first 24 hours of an ear infection or other common illness.14
An uncomplicated febrile seizure usually lasts only a few minutes when the body becomes stiff, the eyes may roll back and one limb or or whole body trembles or shakes, followed by a short period of disorientation and drowsiness. Simple febrile seizures triggered by a fever last only a few seconds or minutes and are not thought to cause lasting harm.
However, if a seizure occurs after vaccination or administration of a drug and, especially, if it lasts longer than a few minutes or is followed by unconsciousness, it may not be a simple febrile seizure.15 16 Seizures after vaccination or during an infection may be a symptom of brain inflammation (encephalitis) and requires immediate emergency treatment.17
Doctors advise that immediate medical attention should be sought when a child experiences a first seizure or any kind, whether it is associated with a fever or not, including calling an ambulance or, if the seizure stops before it arrives, taking the children to the emergency room for evaluation.
Most of the time, the appearance of a simple fever in a child or adult is not cause for alarm but is evidence that the body responding as it should to a challenge that requires an effective immune response. Fever is an integral part of the immune system’s natural ability to achieve optimum immune function. Unwarranted fear of fever has often led to use of unsafe fever reducing drugs by children and adults.
As Edda West, founder of Vaccine Choice Canada pointed out in 2008:
Our mistrust of natural processes, and reliance on drug oriented medicine has obscured our understanding of the importance of childhood illnesses and the necessity of fever as a vital aspect of the maturation of the immune system enabling a strong & resilient foundation of health to evolve. When we discard the old fears and lift the veil of ignorance, we are then empowered to see with our innate intelligence, the real picture unfolding in front of us—and recognize that the artificial manipulation of children’s immune systems, via mass vaccination programs, indiscriminate use of antipyretics and antibiotics, rather than protecting, is threatening their health—their future.18
1 Fever Plays Vital Role in Immune Response. Infection Control Today Nov. 2, 2011.
2 Nalin P. What Causes a Fever? Scientific American Nov. 21, 2005.
3 Laupland K. Fever In The Critically Ill Medical Patient. Critical Care Medicine 2009; 37(7): S273-S278.
4 White B, Mavor S. Fever in Children: A Blessing in Disguise. Mercola.com Dec. 17, 2000.
5 Sewell R. Medicine 101: The Science Behind A Fever. Canadian Pharmacy Meds.
6 Jones C. Fever Phobia. Science-Based Medicine Dec. 21, 2012.
7 U.S. National Library of Medicine. Fever. National Institutes of Health Aug. 30, 2014.
8 Richardson M, Pursell E. Who’s Afraid of Fever? Archives of Disease in Childhood 2015; 100(9).
9 Tylenol. DrugWatch.com Oct. 16, 2015.
10 AAP. Treating a Fever Without Medicine. HealthyChildren.org Nov. 21, 2015.
11 Mercola J. How To Kill A Cold, Starve A Fever And When You Must Absolutely See A Doctor. Mercola.com Oct. 26, 2010.
12 Mayo Clinic. Fever: First Aid. MayoClinic.org Apr. 15, 2015.
13 U.S. National Library of Medicine. Meningitis. NCBI.
14 U.S. National Library of Medicine. Febrile Seizures. Medline Plus Feb. 26, 2014.
15 Principi N, Esposito S. Vaccines and Febrile Seizures. Exp Rev Vacc 2013; 12(8): 885-892.
16 U.S. Centers for Disease Control and Prevention. Vaccines and Febrile Seizures. CDC.gov Aug. 28, 2015.
17 U.S. National Library of Medicine. Encephalitis: Symptoms (Infants) and Emergency Symptoms. Medline Plus Aug. 30, 2014.
18 West E. Is Fear of Fever Hurting Our Children? Vaccine Choice Canada Nov. 26, 2008.