Fever Phobia

Fever is a mighty engine which Nature brings into the world for conquest of her enemies.”

— Thomas Sydenham


The occasional abnormal elevation in body temperature associated with infection is as much a part of the human condition as abstract thought or the desire to lose weight without exercise or cutting calories. Commonly known as fever, this powerful yet misunderstood physiologic response has been documented in a variety of animal species including fish, reptiles and of course humans. We have all had fever at least once in our lives, and probably several times. And many of us have undoubtedly spent a few anxious nights cradling febrile little ones, afraid more of the repercussions of the fever itself than the potential sequelae of the underlying cause.

Along those lines, fever is one of the most common reasons for parents to seek medical care for their children, with roughly a third of pediatric acute care visits related to it, as well as a frequent impetus for late night nursing calls to sleepy hospitalists. Actually only about half of after-hours calls are about fever but who’s counting. Unfortunately most medical professionals, including many pediatricians, have a poor understanding of the pathophysiology of fever, and their panicked approach to its management in many children involves unnecessary laboratory tests, imaging studies, and doses of broad spectrum antibiotics. It also adds to parental anxiety and helps to establish a vicious cycle as patients of over worried caregivers tend to undergo more aggressive evaluation and treatment.

What isn’t fever?

Any discussion of what fever is must first be tempered by information on what fever isn’t. Fever is not hyperthermia. Hyperthermia is not a physiologic response to infection but instead is overheating despite our thermostat (I’ll get into this in a bit) being set at normal. Hyperthermia occurs when we retain excess heat from an external source, such as when a young child is forgotten in the car on a hot Louisiana Summer day, or when there is overproduction of heat caused by a reaction to certain medications. A diagnosis of hyperthermia carries with it significant risk of direct morbidity and mortality while fever rarely leads to direct harm. Perhaps some of the fear experienced by the mere thought of febrile children stems from the muddling of these two concepts. This post is about fever, not hyperthermia.

The Physiology of Temperature

The temperature of our bodies is amazingly steady despite significant variations in environmental temperature and physical exertion. This is achieved by an amazing interplay of our autonomic nervous and endocrine systems as well as some evolved instinctive behaviors. The thermoregulatory center of our bodies is the hypothalamus. It can be thought of as our “thermostat” and it maintains a temperature set point by balancing heat production with heat loss. We primarily produce heat by metabolic activity in the liver and muscle while heat is lost through the skin and lungs.

What is fever?

Fever occurs when our set point is raised above the current body temperature and is a homeostatic process. When the body is exposed to infectious organisms such as viruses and bacteria, a number of so-called pyrogens (another name for fever is pyrexia) are produced as part of the inflammatory response. These pyrogens can then act on the thermostat to raise the temperature set point by release of prostaglandin, primarily prostaglandin E2.

Now here comes the really fascinating stuff. Once the set point is raised, heat generating actions are taken by the body to raise core temperature to that new point and we enter the “chill” phase of fever. We increase cellular metabolism in a number of areas but the most dramatic response occurs in skeletal muscle. We conserve heat by constricting the blood vessels in our skin, decreasing the supply of warm blood to our extremities. In other words, we feel cold and we shiver. The evolved behavioral response should be obvious at this point. We grab the blankets and crank up the heat. All this happens before we actually have a measurable increase in our body temperature.

How high our body temperature goes with fever is limited by a number of factors, largely genetic or specific to the inciting infectious organism. But there is a negative feedback mechanism that involves production of cryogens which serves to keep things in check. When the illness resolves, or when antipyretic medications that target production of prostaglandins are given, the temperature set point returns to normal. This leads to the “flush” phase of fever. The blood vessels in our skin open up, bringing more warm blood to the surface to increase dissipation of heat via sweating, our cellular metabolism decreases, and we kick off the blankets. No more fever.

What is fever phobia?

When I take care of patients with fever I see a wide variety of parental reactions, ranging from reasonable concern to extreme worry, even terror occasionally. My personal experience is that the typical response is much closer to the latter. I always make a point to ask parents what they are worried about and I get a range of responses, from continued discomfort to brain damage to death. Again, anecdotal experience has led me to believe that folks are far more worried about fictional serious complications of fever than mere fussiness or malaise. At the core of these concerns is the misconception that the elevation in temperature represents a potentially dangerous disease in and of itself rather than a relatively benign symptom resulting from an infectious process. This is fever phobia and it has the potential for serious, even deadly, repercussions.

The number of blatant misconceptions regarding childhood fever is truly staggering. Since the 1980’s, when Barton Schmitt published the seminal paper on the subject of fever phobia in the American Journal of Diseases of Children, there have been several additional studies confirming and cataloging the causative factors and potentially dangerous resulting behaviors. These studies have shown that fever phobia exists in both parents and pediatric medical professionals.

Schmitt found that 94% of parents thought that fever could cause harmful side effects. It can’t, except very rarely in extremely critically ill children secondary to the increased metabolic demand. 63% of parents were very worried about serious direct harm from fever with 18% believing that brain damage could occur with temperatures less than 102 degrees. 16% believed that temperatures could rise to 110 to 120 degrees if untreated. Fever does not cause brain damage, hearing loss, blindness, etc. And it cannot rise above the rare 107 degrees (remember those cryogens?). Even then it does not directly harm the body. I imagine that one would feel pretty miserable however.

But that was in 1980. Things have changed, right? Not really. A 2001 paper revisiting fever phobia published in Pediatrics revealed that 91% of caregivers thought fever could cause harmful side effects including seizure (32%), brain damage (21%) and death (14%). Coma and blindness also made the list. With the exception of febrile seizures, a common and benign entity seen only in young children, fever just doesn’t do these things.

More than half of caregivers were very worried about significant harm with many worried even about temperatures less than 100 degrees. That isn’t considered a fever by pediatricians. More than half of caregivers checked temperature every hour (or more frequently!) during illness. My memory fails me, but I imagine two dozen rectal temperatures in a day is uncomfortable, and they certainly can cause injury. Taking the temperature of an older child may not require a rectal thermometer, but it is excessive, and children need sleep. But 85% of caregivers would wake sleeping children to give antipyretics (please don’t do that). A quarter of caregivers gave antipyretics for temperatures not considered a fever. Many children with temperatures of even 101 or 102 degrees aren’t symptomatic.

Here is where it gets dangerous. More than half of caregivers dosed antipyretic medications too frequently. Many studies done since 2001 have confirmed that parents frequently dose antipyretics incorrectly, putting their children at risk for serious liver and kidney injury. Unwarranted fear of fever leads to unnecessary medications, and if a dose that is too high is given too frequently, well, you get the picture. Nearly three quarters of caregivers admitted to the use of sponging to reduce fever, a practice which is ineffective even when done in a safe way. Two thirds of these caregivers however sponged incorrectly, using cool or cold water, or even rubbing alcohol. The former can causes discomfort and impede the ability to dissipate heat by constricting skin blood vessels, and the latter can cause toxicity and death.

Whose fault is fever phobia?

Parental fever phobia, which exists across socioeconomic classes, is strongly reinforced by the actions of pediatric medical professionals who are widely considered to be primary resources on the subject. Fever is often the first symptom we ask about and the first vital sign we check. We emphasize that our lab and imaging investigations are necessary because of the elevated temperature. We tend to treat any and all fever with antipyretics like acetaminophen and ibuprofen. Fever also plays a large role in discharge instructions from emergency departments and inpatient facilities, which commonly contain warnings to call or return if fever develops or persists.

Yet we often give incomplete, inconsistent and even incorrect information. That is when we actually give any information at all. In the early 1990’s, May and Bauchner looked into the role pediatricians play in fostering the development of fever phobia. They performed a survey of pediatricians in Massachusetts which found that 10% almost never discussed the definition of fever, 25% almost never discussed the effects of fever and 15% almost never discussed the cause of fever.

The survey revealed incongruence between the education of families and the practice of pediatricians. Pediatricians for the most part agreed that parents should not wake a sleeping child to check temperature or give antipyretics, but the majority advocated treating low and likely asymptomatic temperatures. These mixed messages remain in existence today. But it gets worse. In the same survey, May and Bauchner found 65% of pediatricians believed that fever could be dangerous with 21% listing brain damage as a potential complication. Just over a quarter of them listed death as a possible result of the fever itself, not the disease actually causing the fever.

In 2000, Mayoral et all published survey results in Pediatrics revealing that nearly a decade later pediatricians still commonly held false beliefs about fever and its management. 50% of the respondents recommended alternating antipyretics for instance. This generally mean giving acetaminophen and ibuprofen three hours apart, typically scheduling them until the child has recovered from the illness in order to prevent fever rather than just using them as fever occurs. Nearly a third of the pediatricians in the survey cited a nonexistent policy of the American Academy of Pediatrics as support of the practice. The AAP actually strongly recommends against such an approach to fever as it has not been shown to be more effective and it increases the likelihood of dosing errors.

Pediatricians tend to only discuss fever when children are sick, and when they do discuss it at well-child visits it usually involves warnings of when to seek medical care without education on the many commonly held false beliefs. Our emphasis of fever without accurately explaining what fever is leaves parents anxious and forces them to rely on alternative sources of information, such as the internet, which I’m told pretty much allows anybody to publish just about anything.

According to The Baby Adjustors,

If you child has a fever and acts abnormally, call your family chiropractor. Your child may be suffering from a spinal subluxation. This condition interferes with normal body function and can cause many childhood symptoms, including a fever.

Or your child may have meningitis that can progress to death in a matter of hours but that is just my Western medical bias. They don’t even explain what “acts abnormally” means. If your kid has a fever and is a Saints fan, he may have a subluxation. But this isn’t about how painfully bad and dangerous irregular medical advice can be, it is about how painfully bad and even sometimes dangerous real medical advice can be and how it can lead to parents and other caregivers treating benign childhood fever as a medical emergency.

Some have described fever as our friend. There is merit to the idea that fever has a beneficial purpose but it remains somewhat controversial. Elevating our core body temperature in response to infection is a primitive and almost universal response, seen even in cold-blooded species. Lizards have been observed staying in the sun longer and fish seeking out warmer water when ill for example. This implies at least that there is some degree of survival advantage in being able to develop a fever.

Some bacteria and viruses do grow poorly when exposed to higher temperatures. Iron is required for growth by many pathogenic bacteria, and it appears that fever decreases availability of it in the blood. Test tube studies have shown that elevated temperatures may increase the activity of various components of the immune system. There are a few non-primate experiments, particularly in rats and rabbits, that have shown improved outcomes with fever and even some human studies showing prolonged symptoms when fever is treated aggressively.

But everything seems to increase the activity of various components of the immune system in test tubes, and those studies were small and difficult to extrapolate to all humans or to all specific fever causing infections. Plus there is also data showing that the immune system may actually become impaired during high fevers above 104-105 degrees. And there is also evidence in animals and human patients that raises concerns of poorer outcomes from some illnesses, particularly in critically ill patients, with very high fever. It is a mixed picture essentially and the jury is still out. Regardless, any benefit of fever is likely so minimal that it would not preclude treatment of a miserable toddler with a temperature of 102.

Does this all mean that fever shouldn’t be taken seriously? Of course it doesn’t. In certain patient populations, fever requires immediate intervention. Very young or unimmunized children are at high risk for severe infections of the blood and brain. Febrile neonates and immune compromised patients, such as in Sickle Cell disease for just one of many examples, require laboratory investigation and even empiric antibiotic coverage even if they are completely well appearing. Prolonged and unexplained fever that lasts longer than a week, also justifies a work up. Fever is simply a clue, sometimes the only clue, that there is an infection going on. Thankfully in the vast majority of children, and I mean the vast majority, the infection is self-limited and viral.

Most pediatricians, emergency room doctors, nurse practitioners, and other medical professionals that care for children are well meaning folks who practice good medicine most of the time. But we are human and we are vulnerable to all of the weaknesses inherent in being human. Why are we so afraid of fever? Perhaps because of the biases, logical fallacies, and intellectual stumbling blocks that plague us all to varying degrees, particularly during such complicated endeavors as the practice of medicine. Or is it that we are simply parroting behaviors learned during impressionable years as medical learners.

Old habits are infamously hard to break in medicine. There will always be a subjective component to what I do, an art to the practice of medicine. But the science of medicine, preferably bolstered by the acquisition of good critical thinking skills, is necessary to recover from or avoid problems like fever phobia.



Posted in: Science and Medicine

Leave a Comment (39) ↓

39 thoughts on “Fever Phobia

  1. carassius says:

    Huh…It’s been awhile since I’ve thought about this or reviewed a textbook (i’m a veterinarian) but I thought it was interleukin 1 that changed the setpoint of the hypothalamus.

    I’m now remembering nightmarish diagrams of immune response complexes filling chalkboards…so i’ll admit I could be remembering incorrectly.

  2. mousethatroared says:

    Sorry, I haven’t read the whole article. I want to drop a comment before I rush off, I want to come back and read the rest of the article more closely, because it seems I have a misunderstanding of fevers.

    As a parent I would answer the question of what I fear from fever.

    1) I was taught in high school health class (1982) that high fevers, over 106 (? maybe I’m not good at remembering numbers) caused our “proteins” to unravel and can cause brain damage. We even watch a film on a man whose’s long term memory was damage after an illness with a high fever. So I always medicate a fever over 102, 103. Even if the unraveling proteins in a myth. My kids (and I) are always miserable with a fever in that range, so I don’t think I behave any differently.

    2) Strep – I don’t fear strep in ALL fevers, but if a higher fever goes on for a few days, we’re in to the doctor for a strep test, because strep is a bummer, can possibly be dangerous and it’s easy for everyone to catch (more misery all round)

    3) Menengitis – It’s just when you have a really sick younger kid on your hands with a higher fever, it’s hard to know what symptoms they are actually having. Do they have a stiff neck or sore throat or is it body aches? Do they have a headache? Communication is difficult with a sick child.

  3. tgobbi says:

    Clay mentions “The Baby Adjusters.”

    At the risk of appearing obsessed with chiropractic (a distinct possibility) I’d like to say a word or two about the founders of this repugnant outfit that I first heard about back in the mid-90s when it was featured on the ABC “20/20″ television program about chiropractic “pediatrics.” I had taped that show and have shown it to a number of friends, including medical professionals, on a number of occasions. It was damning of chiropractic in general and their approach to pediatrics in particular. Two horror stories were shown: chiropractic-induced irreversible crippling of one child and chiropractic-induced death of another, both entirely preventable with mainstream medical intervention. The program triggered an avalanche of letters from “doctors” of chiropractic from all over the U.S. The bulk of the letters arrived BEFORE the show aired!

    Among many egregious affronts to medicine, science and reason was a section about “doctors” Jennifer and Palmer (yes, he comes from a long line of DCs – hence the name) Peet. Ms. Peet was definitely the more vocal of the pair and offered quite a bit of “expert, advice – all of it, of course, wrong.

    For example, she insisted that 95% of kids have those pesky, but nonexistent, chiropractic subluxations and that many die from them! Also, she was shown some x-rays of a child’s spine. I don’t recall what the condition was that had been diagnosed by the child’s physician but the host wanted Ms. Peet to offer her take on what they meant. These x-rays had been taken by a medically trained radiologist but Ms. Peet looked at them from several angles and proclaimed that she couldn’t figure them out because they were “terrible x-rays!” She promised the host that she would study the films and get back to him. At last report her response was still forthcoming.

    She struck me as smug, alarmist and generally obnoxious with an attitude of superiority over “mere medical experts.” (My words, not hers).

    According to the link Clay provides, it appears that this “Baby Adjuster” survives to this day.

  4. Janet says:

    Why do we fear fever?

    “Or your child may have meningitis that can progress to death in a matter of hours”

    Or, if you’re my age, you may have a mother who survived scarlet fever (many didn’t) and taught you to fear fever in children above all else.

    While raising four children in the 70’s and 80’s, I was clearly told (mostly by Family Practice docs–rarely saw pediatricians) not to fuss about (and not to call in the middle of the night!) for anything under 102 degrees. One child was particularly plagued by frequent fevers around 101 or 102. I was always calling and taking him in to the doctor–who hasn’t read about some child dying of meningitis?. One day, the doc sat down and explained much of what you have written to me and convinced me I actually had a child with a very healthy immune system who was able to fight off infection very well. We had few office visits after that.

    It may take a few minutes to have such a talk, but much time can be saved in the long run.

    One other thing. I’m sure glad we didn’t have the internet then because I may have fallen for some of these sCAMS in those days, although the altie rage hadn’t really taken off so much then.

  5. whamo says:

    I work with children and most parents (especially families where both parents are doctors/medical) dose their children up with fever reducers so they won’t miss work.

  6. dani681 says:

    So a fever in a newborn is an occasion to freak out, and a fever in an older child should cause no concern at all. Has the typical medical response to newborn fever really been studied for effectiveness? My daughter was 10 days old when I noticed a fever during a midnight feeding. If I recall, it was about 102°. I called the overnight nurse (this is the procedure I was told to do with any fever before 2 months old) and was told to take my daughter to the emergency room immediately. While there, they performed the following: blood draw, catheter, spinal tap, and chest x-ray. Then they medicated her with both acetaminophen and ibuprofen, hooked her up to an antibiotic IV, and admitted her (and, by extension, me, the nursing mother) to the NICU.

    Three days later, the fever went away on its own. She was required to be hooked up to the antibiotics for a total of four days, since the first blood sample came back with a suspected contamination of staph (the second sample was clean). She tested positive for enterovirus in her spinal fluid, so eventually the diagnosis became a suspected case of viral meningitis, with no symptoms other than fever. And I was with her the entire time, having to witness a spinal tap of a 6 lb infant, recording every feeding and weighing every diaper, and running home for just a few minutes every night to tuck my son into bed.

    At the time, everything was very scary, and all worst-possible scenarios were discussed. In the end, no one could even tell me why she developed nothing more than a fever, despite the presence of the enterovirus. Meanwhile, they all lauded me for my vigilance in detecting the fever, and concluded it must be because I was a “seasoned mother.” After the ordeal was over, I began to wonder if I hadn’t been so good at detecting fevers, we never would have gone through it in the first place. And she still would have recovered.

    Where is the line drawn for fever mania? Given her age, she was completely unvaccinated – however, even a 2-month old after the first round of vaccines has not received protection for all nefarious diseases. But at 2 months, we are instructed to medicate at home as needed for discomfort due to fever.

    1. Harriet Hall says:


      I went through exactly your same experience with one of my babies. It turned out to be nothing but a virus, and in retrospect nothing would have happened if we had not taken her to the hospital. But as an MD I knew “the rest of the story” – there was no way to predict that it would turn out to be a virus, and if it had been something serious like a bacterial meningitis she might have died or been permanently disabled. The diagnostic workup and IV antibiotics were a necessary precaution, and I don’t regret it for a minute. The 2 month line is an arbitrary guideline based on the much higher risk below that age.

  7. elburto says:

    I experienced parents calling up and practically shrieking *Bradley’s temperature is 38 DEGREES! What should I DO?”

    So I’d ask “What kind of symptoms does he have?”, to be met with “He’s too HOT!”

    So I’d ask about symptoms again. Was he listless, puking, sweating, did he have a pinprick non-blanching rash, was he complaining of any pain? If it was an infant was she still producing wet nappies and taking milk?

    And I swear, the majority of caregivers reported that their kids were “Normal, running about” or “Happily taking bottles, active and alert”. Not one, but THREE mothers had affixed flexible forehead thermometers to their child’s foreheads in order to constantly monitor them!

    Feverphobia must be tackled through education. Like you said, frequent jabs with a thermometer are not fun, and the fear and stress gets passed onto the kids.

  8. A little humor:

    Of course, you don’t need to be a physician to know what the most effective antipyretic is: More Cowbell.

    What is the opposite of Fever Phobia? Is it Fever Fever?

  9. Clay Jones says:


    Fever is never an occasion to freak out but I hear you. And fever is always a concern because it is a clue that in most cases an infection is present. What we do with that concern varies based on a number of variables, some of which I mentioned in the post. But for most kids who have received at least their 2, 4 and 6 month shots very little “work up” is required. Just a good exam and history.

    There is a lot of nuance to the question of what to do about fever in vulnerable populations such as neonate and unimmunized or partially immunized toddlers. There is good evidence to support full diagnostic evaluations, including lumbar puncture for evaluation of spinal fluid, and empiric antibiotics in children less than 28 days. In kids older than 28 days there is wiggle room.

    We don’t use the 2 month rule universally anymore. If I have a 6 week old infant with a fever of 104 with clinical evidence of bronchiolitis, for instance, and who is sick but non-toxic, I won’t do an LP. Evidence supports that and a few others ways to get out of the tap. But, in general, a neonate or partionally/not immunized young infant/toddler with temp over 102.2F has about a ten percent chance of a serious bacterial infection (kidney, blood, brain). That is why we do what we do. There is protection from the 2 month shots but not enough to decrease the risk enough to blow off fever. After the 4 month shots, and certainly after the 6 month shots, the risk dramatically lowers. I don’t do any work up except urine in kids who have received them and are non-toxic. There is a lot more nuance to all this. Too much to get into in this setting.

    It sounds like you got good medical care with poor communication. So bad medical care perhaps then. There is risk to every medical intervention. False positive blood cultures occur in roughly 2-3 percent, and it can keep kids in the hospital as it did for you. But it might not have been a contaminant. And viral meningitis, although it tends to be milder than bacterial, still can cause severe morbidity and even mortality.

    I disagree with advice to simply medicate fever in a 2-month-old. They should be evaluated. It doesn’t have to be in the ED, but it should be done.


    “strep throat” phobia is post worthy itself.

  10. Clay Jones says:

    @ Karl,

    I included a picture of “the Bruce Dickinson” in a fever lecture I gave at a nursing conference, and made a reference to needing more cowbell. Very few of those in the audience knew what I was talking about. I’m apparently very old. Perhaps I’ll include something about “Bieber Fever” next time. Certainly they won’t know about Pacman induced pyrexia.

  11. DugganSC says:

    The perennial question, is aspirin still verboten for children? When I was growing up, “everyone knew” that you didn’t give aspirin to a child with a fever with some people taking a more extreme stance that aspirin was unacceptable for a fever for anyone. The general fear stated was Reye’s Syndrome, but I’ve also seen reports that the fear of Reye’s Syndrome is all based one one test done back in the 80s whose results have since been disputed and that we’re chasing paper tigers (the rightness of banning aspirin has generally been justified by the drop of Reye’s Syndrome cases after they made their announcement, but I’ve also seen data seemingly indicating that the number of Reye’s Syndrome cases was dropping before they made the announcement).

    So, is there any proven risk of aspirin use on fevers for children?

  12. The Dave says:

    A couple things:

    First, As a father of 3 young children (6, 4, 4mos) we have to deal this fever from time to time. Our first pediatrician (got a new one because we moved out of state) was really good and told us to let the fever run its course and only administer antipyretics if the child is uncomfortable due to the fever, just to relieve the suffering. But she also told us to do the alternating of the ibuprofen and acetiminophen. Fortunately we haven’t had to deal with really high fevers, so that has seemed to be a good plan, without much induced fear.

    Second, recently in my self-care therapeutics class in pharmacy school, we were told the following for when to refer a patient to contact their PCP:
    Adult with temperature >103°F or >48 hours
    Child ≥ 2 yo >103°F or >48 hours
    Child >13-24 mo >103°F or >24 hours
    Child >6-12 mo >102°F or >24 hours
    Child 3-6 months temp >101°F or >24 hours
    Child 100.4°F or >24 hours

    Would you concur with those recommendations, or would there be some better advice concerning fever? Thank you for the article

  13. nybgrus says:

    Thank you for this post Dr. Clay.

    I spent a week in pediatric ER a little over a month ago. I’ll let you guess what the most common patient complaint was…

    I advised every single patient on discharge that a fever is nothing to be afraid of and that as long as the child was not miserable, looking really sick (I explained to them what we mean by “sick” or “toxic” and how we are trained to see that) to simply leave it be, regardless of the number. If the child is miserable, can’t sleep, etc then sure, medicate. But only when miserable and never wake them up to give them antipyretics. I explained that if they were sleeping that meant that no matter how high the fever was it didn’t matter. I also explained febrile seizures and how the risk of them does not go down if you treat the fever.

    This seemed to have a positive effect though obviously I can’t comment on follow up.

    I also mentioned the data showing lack of efficacy for cough and cold remedies in children under 6, minimal in those under 12, and questionable even in adults to my attending (I also talked about over dosing in cases as you described). He actually become somewhat angry and defensive and called the data BS and said that it most certainly does help since “in his experience” he had seen it work many many times (he had been in pediatrics practice of some kind for going on a few decades at least). Needless to say I dropped the conversation with him, but it speaks to the difficulty in change in medical practice.

    As for aspirin with fevers… my understanding is the Reye’s syndrome is a real, albeit rare, entity and that it has to do with giving aspirin during viral infections. It is not about treating the fever per se, but the fact that in the majority of cases fever means virus and that is the danger. I am also under the impression that it is not because of an absolute risk that we recommend against it, but because things like ibuprofen and acetominophen have much lower if not zero risk and the same effects, so why risk it at all? I also seem to recall that even adults can be susceptible to Reye’s and as such are also advised against taking aspirin during febrile illness but the risk is even lower and nobody seems to care too much about it, even though the principle is the same. I personally never take aspirin for anything since I reckon the side effects to be too great in light of other drugs that can be taken instead.

    Pediatrics is not my forte (though I somehow passed my rotation with honors), so does all of that sound about right Dr. Clay?

  14. @ Clay,

    What about Feline protractile claw leceration induced pyrexia?

  15. The Dave says:


    As far as I understand it (and please correct me if I’m wrong) Aspirin is very rarely used in pediatric patients because of the concerns for the blood-thinning, risk of Reyes Syndrome, and other toxic effects. It can be used, however, under direct medical supervision. My self-care therapeutics class (mentioned above) says “Do not use aspirin to treat a child or teenager who has a fever, flu symptoms, or chicken pox without first talking to the child’s doctor. ” and that it is dosed at 60mg/year of age q4-6hrs not to exceed 600mg in one day.

  16. @ Clay,
    I guess any Dr. Johnny Fever references would have gone right over their heads as well.

  17. nybgrus says:


    That is usually caused by Bartonella henselea and should still be treated with tylenol and advil instead of aspirin for the remaining toxicity concerns. That and because Ted Nugent is crazy.

    Johnny Fever on the other hand is indeed out of my frame of reference.


    There are instances were aspirin treatment is preferred in children. The one that comes to mind is Kawasaki’s disease, in which case extremely high doses of aspirin are given as the first round of treatment. That disease does present with a fever but it an autoimmune disease, not an infection.

  18. MTDoc says:

    Back when I began Medicine, “baby aspirin” was the preferred antipyretic. Then they discovered a “co-incidence” with Reyes Syndrome. Aspirin was very effective in reducing fever, and I always wondered if Reyes Syndrome was due to the aspirin or the effective fever reduction.
    In my country practice the patient almost always saw the same physician. We saw very little “fever phobia” after the first visit when we explained that fever was the body’s response to infection, most of which were harmless. We could then focus on the cause and treat appropriately.
    Modern medicine is totally fragmented, having rejected the family physician concept I grew up with. The Clinic I started many years ago is now run by a hospital. Patients see whoever is available, are referred to the ER nights and weekends, and when hospitalized never see their regular doctor, even if they have been able to establish one. (Sorry, didn’t mean to get off topic)

  19. mousethatroared says:

    @Clay Jones – Ha! :) You might have a hard time convincing me that my fear of strep throat is unreasonable (although I won’t speak for whether some other parents over-react or not). I’ve had strep three times and I hate it! The last time I had strep, I gave it to my daughter…then my son got it and my husband. That’s a lot of doctor visits, antibiotics to administer and sick grumpy folks to deal with. Also my sister had rheumatic fever following a strep infection as a child AND one of my heros, Jim Henson, died from a strep infection, when he delayed seeing a doctor. It’s just nothing to mess with, in my mind.

    That said, I’ve never called a doctor in the middle of the night for anything. We have a good after hours clinics and pediatric ER, if I felt a child was in danger from an illness, I would take them there. And if the doctor runs a strep test and it’s negative, I’m good. I don’t fuss for antibiotics for a negative strep result. So maybe I’m not that phobic.

  20. mousethatroared says:

    nybgrus – You just made me even more happy with our pediatrician, who was very clear with me that I shouldn’t give cough/cold medicine to the children because they* don’t work and there have been cases of overdose with “bad outcomes”.

    Our pediatrician recommended warms water with lemon and honey for a cough. Very hard to overdose, gets them some liquids, is a bit soothing and cuts down on the sense parental helplessness.

    *The medicines, not the children…although actually the children don’t work much either. :)

  21. nybgrus says:

    Those lazy children! Man, those repressive child labor laws the damned liberals forced down our throats….

    In any event, a negative rapid strep test actually has a low enough negative predictive value that it warrants a more thorough culture to be sure it isn’t strep and then treat with Abx if positively diagnosed. You have about 10 days from the onset of symptoms to treat and prevent rheumatic fever. But with ~30% false negatives from the rapid test, we still recommend doing a confirmatory test since the sequelae of RF are not worth it. A positive test is enough to treat though, which is why we use still use it as an effective first cheap screen.

  22. mousethatroared says:

    nybrgus – Ha! Yeah, damn socialists.*

    Maybe I should have said, the Ped office always sends the strep test out for the more reliable test and calls with the result two to three days later.

    *Actually, I shouldn’t gripe about the kids, they do actually work hard in school. I just wish they would pick up their socks. :)

  23. Clay Jones says:

    Aspirin = bad unless you have rheumatologic condition or Kawasaki and no better than acetaminophen and ibuprofen anyway for fever, pain, etc.

    cough medicine = bad; honey = good as long as over a year of age

    Thermometer stickers = useless unless your child is also a fish tank

    Jim Henson didn’t die of strep throat, he died of group a strep sepsis from what looks like group a strep pneumonia, an uncommon but often very severe form of community acquired pneumonia. I don’t have much info to be honest but he might have had Lemierre’s. I’m just shootin’ from the hip though and would need to dig. His case should not be a reason for a parent to fear strep throat. Fine, my next post will be on this…..maybe. I want to write about the 2nd most useless test in medicine really bad though. What is the first most useless you ask? The APGAR. My apologies Virginia.

    @ The Dave, I disagree with those recommendations but it is hard to have a easy set that takes into account different ages and multiple variables so many folks go with being over cautious. But then again those recs are not cautious enough in some ways. It is just too nuanced an issue.

  24. DugganSC says:


    Not for coughing, but an effective home treatment for sore throats is cayenne pepper sprinkled in a hot drink. As I understand it, it has an anti-inflammatory effect, plus the brief burn from the pepper distracts you from the pain in your throat, making it feel better afterwards. It’s particularly good in hot chocolate, which was actually part of the original recipe in South America (albeit without sugar back then, meaning it was bitter and spicy).

    Thank you all for the responses regarding aspirin. It’s one of those things where, on one hand, I couldn’t find any research results supporting the link past that initial one, but on the other hand, it had the feel of a “modern medicine is so smug that it forgot to actually check its results” story. I suppose that even a very minor link would be enough to contraindicate it, although the very low risk level means that parents who slip up shouldn’t beat themselves up for it (it reminds me of the cases of moderate alcohol consumption during pregnancy, or marrying your first cousin. Neither has a significant negative effect, but people avoid them anyhow because a) they’ve been told all of their life that it’s a horrible thing to do with the risks blown out of proportion, and b) it is a risk, however minor, and it’s easier to skip those steps than more rigorous practices such as proper nutrition and regular exercise.

  25. Clay Jones says:

    There is some controversy I believe over Reye syndrome. It’s very rare these days. Used to be more common. Is it specifically related to aspirin, and we have cut that out leading to the decrease in incidence? Or were these cases actually caused by some other inborn error of metabolism, things we now have names for and diagnose earlier with newborn screens and such. I don’t know, but I’m still not giving my kids aspirin.

  26. The Dave says:

    @Clay Jones:

    “I disagree with those recommendations but it is hard to have a easy set that takes into account different ages and multiple variables so many folks go with being over cautious. But then again those recs are not cautious enough in some ways. It is just too nuanced an issue.”

    Thanks for the response. My 4 month old had his checkup today and I mentioned this post and we discussed it. He said, except for infants under 3mos old, the temperature doesn’t matter, just how long the fever has been lasting. He said if it has been going for 5 days, then you really need to see a doctor. He agreed with the 100.4* for infants under 3mos.

    I’m not sure of the sources, but my professor gave us those recommendations from the point of view that if we were a retail pharmacist and someone comes in asking for fever medicine, these are the parameters when we should recommend a doctor visit, as opposed to self-care (OTC’s, etc.)

  27. Clay Jones says:

    I agree that degree of fever isn’t helpful in older kids. There are some hospitals (mine) and physicians that place importance on a fever of 105F. This is based on pre-Prevnar data showing an association with higher risk of pneumococcal bacteremia in children. I don’t consider it a risk factor anymore in immunized kids and in partially or unimmunized children I use a fever of 102 (technically 102.2 but that is just silly) as the cutoff for increased risk.

  28. Clay Jones says:

    Just reread my comment. So degree of fever is important but 106 is not more likely to be associated with bacteremia than 102.

  29. Mark says:

    Love the post. I (Adult ID Doc, worried dad) go through this argument with my spouse (RN, worried mom) every time our little one spikes a temp. I also see rampant overtreatment of fevers in the hospitalized adults I round on. A recent fellow, packed miserably in ice packs, is a nice case in point. Fevers happen for a reason. They are a useful host defense mechanism. Natural selection would have weeded out this response long ago were it not a survival advantage of some sort. Treat the infection (or watch it if viral) and leave the fever be.

  30. pmoran says:

    Febrile children are also often also very miserable, and, for what it is worth, they do seem to perk up after being given paracetamol (or aspirin in the old days). Is there any scientific evidence pertaining to useful symptomatic relief?

    I feel uneasy about a present trend to use other NSAIDS in young children with fever. This is advertised on TV locally, and a paediatrician advised my daughter-in-law to use ibuprofen in conjunction with paracetamol, leading to a bit of a family squabble. Any thoughts?

  31. Clay Jones says:

    @ Pmoran

    Absolutely. I always recommend treating symptomatic fever. Any potential benefit of fever is likely minimal and the acetaminophen and ibuprofen are very safe medications. Nothing is without risk but still the risks are quite low. I didn’t include this in my post, but there is a newish trend to give acetaminophen (paracetamol) at the same time as ibuprofen. This is not supported by evidence of safety or increased efficacy. It is also not recommended to alternate them. There are benefits and risks with each. Tylenol probably kicks in faster and motrin probably works a little longer. But tylenol when overdosed can destroy the liver and motrin, especially when given to a dehydration kid, can ding the kidneys pretty bad. I generally recommend tylenol as first line for fever, and ibuprofen when the issue is more pain/inflammation such as with a bad pharyngitis. Tylenol can be given to kids of any age while ibuprofen should not be given to kids under 6 months.

  32. Alia says:

    I am an example on the contrary tendency. When I was a kid, I almost never got fevers, even if I was really ill. And this was a huge problem for my mother (who’s a nurse and generally has a very healthy approach to elevated temperature) – because when she took me to a doctor, they would usually think along the lines “no fever, then it can’t be serious”. Even if it was acute bronchitis and I was coughing my lungs out. Or kidney infection.

  33. Thanks for the wonderful post. I will share this.

    A doctor should educate patients and parents to direct their concern to important warning signs of an illness. Once the type of illness becomes clear, I often ask the parents or the patient to stop taking the temperature. We should focus on the patient’s comfort level, level of consciousness, respiratory and fluid status. Treat the patient, not the thermometer.

    Ibuprofen and acetaminophen are fine if there is significant pain or discomfort, if used reasonably. If we focus on dosing medications according to the number on the thermometer, we will use far too much medication and lose focus on the above important signs and symptoms.

    An ill child is not necessarily healthier when the temperature is 99, nor is an ill child necessarily sicker when it fluctuates up to 102.

  34. daedalus2u says:

    I have done a lot of reading and thinking about the physiology of fever in the context of autism l

    and mitochondria destruction.

    The symptoms of Reyes Syndrome are characteristic of mitochondria destruction. Fatty liver, fatty kidney, ammonia elevation, encephalopathy.

    In the context of a fever or other immune system activation, the body raises NO levels. In the case of sepsis, NO levels are raised so high that the high NO by itself can cause death through hypotension. NO levels may get as high as a 10 nM/L (yes, 10 nM/L is an extremely high NO level) in the blood stream. The reason physiology does this is to prevent bacteria in the blood stream from forming a biofilm in the vasculature. As bad as bacteria in the blood is, if they form a biofilm it is ~100 times worse.

    During sepsis, the NO level outside the vasculature gets even higher (hemoglobin in the blood is the sink for NO, and is the lowest NO level (normally)). This very high NO level has the effect of raising the ATP level through their combined action on sGC. This very high ATP level has the effect of shutting down mitochondria (which is good because mitochondria can’t function in a high NO environment). This high level of ATP is produced through glycolysis. Physiology also makes you feel weak and crappy. Feeling weak and crappy are important “features” so that you lie in bed and don’t do anything that might consume ATP. What causes the multiple organ death of sepsis (my hypothesis) is when physiology is unable to sustain ATP levels through glycolysis (usually because of lack of glucose after cachexia cannot be sustained) so ATP levels fall and mitochondria turn on in a high NO environment with irreversibly destroys them. If enough mitochondria in a tissue compartment are destroyed, the result is organ failure and death.

    I suspect that a lot of the function of fever is as a signal to each cell to upregulate heat shock proteins which serve to keep the human cells in proteins from denaturing. Viral proteins are very likely less resistant, and there may be human protein-viral protein interactions which lead to degradation of the viral proteins.

    Feeling weak and crappy are important signals to tell you to not use ATP on things less important than staying alive. Blocking those signals lets you use ATP for less important things. If you exceed your capacity to produce ATP through glycolysis, you are setting yourself up for multiple organ failure (my hypothesis).

  35. BillyJoe says:

    Excellent post, but I have one request:
    Please state temperatures in centigrade as well. Your readers come from all the globe!

  36. dani681 says:

    @Harriet and @Clay,

    I appreciate your replies. The topic of fever generally puts a bad taste in my mouth due to the emotionally traumatic experience I had with my daughter. But this post actually makes me feel much better about fever in general. I have no medical background, so I come only from the vantage point of “concerned mother.” If our pediatrician had, even once, discussed the actual physiology of fever (along with the fact that it is nothing to fear), I would have spent all those fever-filled nights sleeping soundly instead of getting up every couple of hours to check temperatures. Without that information from the pediatrician, all I had to go on was a lifetime of television shows, movies, and books that fueled my fever phobia.

    It would also be helpful if some certain deadly diseases did not end in “Fever.” That does nothing to assuage fever phobia for the masses. ;o)

  37. The Dave says:


    Welcome to the blog! (forgive me if you’ve been here a while, I’m not very good at remembering everyone who comments) I’m sure we on this blog (readers and writers alike) are all pleased that the information provided on this blog has been of benefit.

  38. Jan Willem Nienhuys says:

    Fever does not cause brain damage, hearing loss, blindness, etc.

    But doesn’t fever cause confused thinking, delirious behavior, as if dreaming processes are going while one is more
    or less awake? Can anyone explain what’s going on then?

Comments are closed.

%d bloggers like this: