Is a high fever dangerous? Will it cause my child to have a seizure? What about brain damage?
These are the common questions that I see parents asking when they come into the ER. Along with these questions, parents generally also bring in all kinds of myths and misconceptions surrounding fever. Fever in response to infection is good – ALWAYS! The body is much smarter than me or any other doctor and knows best how to care for itself. The primary response of the body to infection (any infection), is to raise the body temperature. Most infections only survive well at body temperature (98.6°F). By increasing the body temperature to above 100°F the body makes it very difficult for infections to thrive. In the setting of a fever, the immune system has time to rid the body of the infection, which normally takes 3-5 days. This is what fever does – and it is GOOD.
This page is meant to explore the many myths and facts surrounding fever, provide useful information about what you can do at home to help your child feel better, and when you should seek medical attention.
Contents
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Myth or Fact?
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You Decide
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Home & Natural Remedies
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Dr. Reynolds Treatment Protocol
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Test Your Knowledge
Myth or Fact?
The body’s great protector.
Myth #1: Fever causes brain damage.
Fever in response to infection does NOT cause brain damage. I have seen plenty of kids that come into the ER with a fever of 106.5°F and they are just as likely to go on to Harvard as the next kid. True, if you are locked in a hot car or playing football in full pads in the 105°F summer heat, you can get brain damage if your temperature rises above 108°F. However both of theses scenarios are environmental – situations when an external heat is applied to the body and causes a dangerous temperature. The body in the normal process of fighting off a routine infection can not, and will not, produce a damaging or dangerous temperature.
Myth #2: Fever causes seizures.
This is NOT true either. Some children have an underlying predisposition that causes them to have a brief seizure when they have a rapid change in their body temperature. The seizures are brief and are NOT harmful in any way. In fact, roughly 3/4 of the kids that have this type of seizure will never have another seizure. However, kids that do not have this disorder (96% of kids) will NEVER have a seizure no matter how high their fever goes or how quickly it rises.
Myth #3: If I reduce my child’s fever, they will get better sooner.
This, again, is FALSE. This is what the makers of Tylenol™ and Motrin™ would like you to believe. However it is undeniably wrong. In studies of children with routine infection those who were treated with fever reducers stayed sick longer. If you think about it – it just makes sense. If the body is making a fever to stop an infection from thriving and you give a medicine to bring the body temperature back down to normal, the infection is likely to start thriving again. This translates into more work for the immune system and a duration of illness that is LONGER if you take a fever reducer.
Now the down side to fever is that it makes you feel very bad. Again, through intelligent design, our body wants us to lay in bed all day long so that all resources and energies can be diverted to getting well. It turns out though that we in Western society are just too busy to take a few days off, rest, and get well. Thus we pop in a few pills, bring the fever down, feel better for a few hours, go on about our business, and then repeat the cycle over and over again. Sure, this may get you through work or your kid through school, but the overall duration of illness is generally longer and you will be sharing your illness with all of your co-workers and your kid with all their classmates.
Myth #4: If the fever gets too high you should put your child in a cool water bath.
I am not sure where this came from, but it is also false. Just think about it (and I don’t just have to think about it, I can remember it from my childhood). You get the flu when you are in grade school. You have fever and pretty much feel miserable. Maybe you have just had an episode or two of vomiting. What you need is a bed, some fluids, and a few days to let your body fight off the flu. Instead, though, you get tossed into a cold bath. Does this make any sense? I can think of no better way to keep your child sick than tossing them into a cold bath when they are suffering from an illness of any kind.
Then there are some who go to the opposite extreme and put their kids into a subarctic sleeping bag after wrapping them in several layers of pajamas. This makes little sense either. Resist the urge to DO something. Just let your child rest, give them a blanket if they need it, and let the body get on with ridding itself of the infection in the best way it knows how (which mind you, is much better than anything we doctors have come up with).
FACT #1: Fever reducers make you feel better.
This is undeniably true. When kids have fever they are fussy, irritable, do not eat well, do not sleep well, and the list goes on. Giving Tylenol™ and/or Motrin™ will make your child feel better although the overall duration of illness may be longer. I suggest using these medications sparingly particularly at bedtime or if kids are refusing to drink any fluids. Kids need both sleep and fluid to get better. If the fever is preventing either of these, then a fever reducer may be indicated. Using these medications every 4-6 hours, around the clock, however, is NOT suggested and both can cause serious side-effects even when used as directed for a prolonged period of time.
Fact #2: High fever is worse than low fever.
This is both fact and myth. In general, minor illnesses (like a cold) will produce a lower fever response (less than 102°F). More serious infections (like pneumonia) will produce a higher fever response (greater than 102°F) This is a generalization though as the flu is a minor illness that may cause fevers as high as 106°F. More important is fever associated with lethargy, difficulty breathing, or severe pain. These types of fevers should, at a minimum, result in a call to your doctor, and probably result in a trip to the ER or doctor’s office.
That being said, often kids with high fever act lethargic, breath faster, and complain of body aches. This is probably another GOOD indication for a fever reducer. If your child has a high fever, looks lethargic, is breathing rapidly, or complaining of aches and pains, you might try a dose of fever reducer. If the fever comes down and they start running around the room like nothing is wrong – well then it’s probably nothing serious.
Fact #3: My doctor wants to see my child when they have a fever.
This in only true if your doctor is more interested in padding his pocketbook than in the health of your child. The absolute worst place to be when you have a minor illness is the doctor’s office. At any given time there are probably children with 5 or 10 different contagious infectious illnesses sitting in the waiting room. If you want your child who has a cold to also have the flu and a stomach virus, then a trip to the waiting room at the doctor’s office is the place for you.
Now there are three reasons fever must be evaluated by a physician:
1. Fever in a baby less than 3 months old.
2. Fever associated with lethargy, difficulty breathing, or severe pain.
3. Fever in kids with a chronic medical condition (like cancer, sickle cell, etc.).
Virtually all other fevers can be managed at home with rest, plenty of fluids, and judicious use of fever reducers.
Fact #4: Fever is good for you.
This should be self-evident by now. Fever is what the body does to heal itself and fight off infection. In this setting it is always good. If you can avoid giving fever reducers to your child, you will probably help your child get better faster. In certain settings judicious use of a fever reducer may be helpful in keeping your child hydrated and well rested. Most kids with fever have a minor illness and a trip to the doctor’s office will do little more than expose them to other contagious infectious diseases and prevent them from getting the rest they need.
You Decide
To treat of not to treat?
There are really three studies regarding fever that I consider critical reading. All three make important conclusions:
- Fever is good.
- Fever is not harmful.
- Treating fever can make things worse.
With that in mind, let’s get started!
The Journal of Pediatrics: 1989
This classic study looks at children with Varicella (Chicken Pox). The sick children were broken into two groups. In group #1, the children received acetaminophen (Tylenol™) for their fever. In group #2 the children received a placebo (no Tylenol™). Interestingly, in the children that received the acetaminophen, the symptoms and overall duration of illness was longer.
The Journal of Pediatrics:1995
This is another classic study that looks at febrile seizure, the risk of recurrence, and the effect of fever reducer medications on preventing recurrence. The conclusion … the risk of recurrence is low (about 20%) and fever reducers have no impact on the risk of recurrence.
This was conducted on patients admitted to the Surgical ICU. Half of the patients were treated with aggressive fever reduction and half were allowed to have a fever. In the half that had aggressive fever reduction there were more days in the hospital, more infections, and 7 patients died (versus only one patient in the group that was not treated for fever). The results from this study were so compelling that they had to stop the study early because it was felt to be unethical to continue putting patients into an aggressive treatment group. The moral of the story … if the body is making a fever it is probably good. Interfere with this response at your own peril.
Home & Natural Remedies
Do they work & are they safe?
Hopefully if you are asking the first part of the question you are also asking the second. Now while the FDA may not be the best regulator of the pharmaceutical industry, it is better than no regulator at all, which is just the situation with all the Natural & Herbal Remedies. There is absolutely no regulation and very little way to know if what you think you are giving your child is actually what your child is getting. There are many examples of innocent supplements containing very harmful substances (like mercury toxins in oyster shell calcium supplements). Unless you have been living in a vacuum you must be aware that anything that comes from China (and many other developing countries) is suspect.
Now that said, I do believe that there is a rational way to select safe products, but the burden of proof should be placed firmly on your own shoulders. You should first make sure that there is some independent evidence that shows some sort of benefit. Then you must find a product that has been independently reviewed and shown not only to contain what the supplier asserts that it contains, but also that it does not contain other harmful substances.
There are basically Four different categories to think about when you consider Home & Natural Remedies
1. Over-the-counter (non-prescription) medications (like Tylenol™)
2. Nutritional Supplements (vitamin C)
3. Naturopathic Remedies (medicinal plants, herbs, foods, etc.)
4. Non-medical Interventions (luke-warm bath, nasal suction, etc.)
So we will look at each category as it applies to fever.
Over-The-Counter Medications
Basically there are 3 medications that fall into this category … Tylenol™, Motrin™, and aspirin. Now for the most part we never use aspirin in kids because of its association with Reye’s Syndrome. Tylenol™ (acetaminophen) and Motrin™ (ibuprofen) on the other hand are commonly used. Again I encourage parents not to use these medications simply because your child has a fever, especially if it is a low fever. However, as mentioned above, there are some times when a fever reducer might help you avoid a trip to the ER or help both you and your child get a much needed night of sleep.
If you choose to use either or both of these medications you should make sure that you use them in the safest and most effective way possible. Now there are two basic strategies:
1. The alternating strategy: This means that you alternate with Tylenol™ and Motrin™ every 3 hours as needed. This way your child can have some medicine every 3 hours (if needed) but only gets the same medicine every 6 hours.
2. The back-up strategy: This means that you first give a dose of Tylenol™ and wait about 45 minutes. If things are not improved, you give a dose of Motrin™. Most parents will find that they mainly give Tylenol™ and only occasionally need to give a dose of Motrin™. This strategy requires a little more work on your part because you must wait at least 4 hours between each dose of Tylenol™ and at least 6 hours between each dose of Motrin™.
Regardless of the strategy you choose make sure you are giving the proper dose of each. Too little will not work and too much can be dangerous.
The Tylenol™ dose is 15mg/kg every 4 hours, as needed for fever.
The Motrin™ dose is 10mg/kg every 6 hours, as needed for fever.
Nutritional Supplements
There are 5 supplements to consider in this category and they surround fever related to infection. The supplements to consider are Vitamin C, Zinc, Vitamin A, DHEA, and High Lactoferrin Whey Protein. There is a great deal of controversy surrounding these supplements and the studies looking at the risk:benefits, especially in kids, are conflicting. In my opinion, these supplements only potentially have a role in those patients who are deficient in one or more of these. If your child eats a normal diet with ample servings of fruits and vegetables, there is little reason to think that they would be deficient in any of the above things. If, however, your child exists mainly on Cheetos and McDonald’s you might give them some consideration. Then as soon as their illness has resolved consider modifying their diet to included lots of of fruits and veggies.
Naturopathic Remedies
There are many Naturopathic / Botanical Remedies for fever and the illnesses that cause them. Those that have at least been researched some are:
1. Elderberry (Sumbucus nigra)
2. Echinacae
3. Garlic
4. North American ginseng (Panax quinquefolium)
5. Kan Jang (Eleutherococcus & Andrographis)
6. Larch Arabinogalactans (Western Larch)
7. Olive Leaf Extract
8. Astralagus (Astralgalus membranaceus)
9. Baptista (Baptista tinctoria)
10. Isatis (Isatis tinctoria & indigotica)
Elderberry
For the most part there is scant or conflicting evidence on the effectiveness of most of these compounds. The one exception is Elderberry or Sumbucus nigra. Extracts from the berry contain many compounds know to have anti-viral and immune supporting properties. Further, in-vitro (in a test tube) tests have shown Elderberry extracts to be effective at preventing the replication of Influenza. Several other studies have gone on to show that patients with influenza are less sick and recover faster when they take Elderberry extracts.
If you are planning to use Elderberry or any of the other botanical/herbal remedies I cannot stress enough that you must spend some time looking into what you are giving your child and where it is coming from. In the vast majority of cases, children will get better just fine on their own. Giving suspect “potions” from unregulated manufacturers has the potential to do more harm than good. Use common sense and your best judgement.
Non-Medical Interventions
This basically involves helping the body lose heat through normal mechanisms. Actively cooling the body is a BAD idea though. So DO NOT place your child in a cold water bath. This is likely to do little more than make them miserable. However, if you remove warm blankets, dress them in light clothing, and use a cool wash cloth on their forehead this will allow you to work with the normal body mechanism to dissipate heat and help the fever come down.
Dr. Reynolds Treatment Guidelines
What I tell my patients in the ER.
Always remember the Hippocratic Oath: “First do no harm.”
Remember that a fever is generally GOOD for your child. Try to avoid the temptation to DO something, unless you have good reason to think that it will benefit your child.
1. Avoid fever reducer medications if at all possible, especially for fevers that are less than 102°F.
2. Consider a fever reducer in these situations:
A. Your child is refusing to drink fluids.
B. Your child is unable to go to sleep.
C. You child is in pain.
D. Your child is breathing rapidly.
E. Your child is lethargic.
3. If after giving a fever reducer A,B,C,D,&E resolve, then it is very unlikely that a trip to the doctor’s office will result in anything other than a painfully long wait in a room full of sick kids ready to exchange their cold and flu symptoms.
4. If your child is having difficulty breathing, is in severe pain of any kind, or is lethargic despite giving a trial of a fever reducer, then a call to your pediatrician or a trip to a health care facility is indicated. Likewise a child who refuses to drink anything for more than 24 hours may be at risk for dehydration and a call to the pediatrician is probably warranted.
5. Remember that you know your child best. If you are uncomfortable, call your doctor. However don’t let parental anxiety and fear overwhelm you. Just because you DO something does not mean that you have done something helpful. Most of the time, the most helpful thing you can do for child, is to do nothing at all.
6. Lastly, these guidelines are for otherwise normal children. If your child has any chronic medical condition (like sickle cell, cancer, etc.) or is less than 3 months old, call your health care provider at the first sign of fever.
Test Your Knowledge
Three kids, three fevers.
This is the section to apply what you have learned to some hypothetical scenarios. Of course the patients are not real but the concept that they represent are. In this section you will meet Alex, Hope, and Kaden. Three patients with three different fevers.
Alex
Alex is a 21 day old neonate who has been previously healthy. He was born a few weeks early but only spent 48 hours in the hospital for routine newborn and maternal postpartum care. Today he has not been himself. He normally bottle-feeds about 2-3 ounces every 2-3 hours. It normally takes him about 30 minutes to finish a feed. After he feeds he is normally playful for a brief time and then takes a nap for about an hour.
Today however, Alex is intermittently fussy. He is only taking about 1/2 an ounce at each feed and his mom thinks he probably spends more time crying than he does sleeping. He is breathing comfortably when he is not fussy and is still making several wet diapers per day. Since Alex is not himself his mother decides to check his temperature under his arm and notes that it is 99.5 degrees F.
1. What should Alex’s mom do next?
A. Call his pediatrician immediately.
B. Rush Alex to the ER.
C. Recheck Alex’s temperature rectally.
D. Give Alex a dose of tylenol.
The most important concept here is that any baby under 3 months of age that has a fever needs to be evaluated by a medical professional. The temperature, as measured under the arm, is generally one degree lower than the actual body temperature. In other words, this mother can approximate the actual body temperature as measured under the arm by adding one degree. By doing this you would get 100.5° F.
Now the official definition of a fever is any temperature above 100.4° F (or 38° C). Thus according to the rule above, this mom suspects that her child has a fever. However, remember that this is just an approximation. Before she rushes her baby to the ER or calls her pediatrician she needs to confirm the actual body temperature. This is easily accomplished by measuring a rectal temperature, which should be done with a different rectal thermometer. To do this she places a small amount of vaseline on the tip of the thermometer and gently insert the tip into her baby’s rectum. The thermometer should go in easily and her baby should not experience any pain. She allows about 3 minutes to get a proper reading.
If the reading is above 100.4° F her baby will need to be evaluated as soon as possible. This mom should call her pediatrician as a first option. However, if the office is closed or she cannot contact her pediatrician in a reasonable amount of time, she will need to take her baby into the ER. Small babies (< 3 months) can get sick quickly if they have a serious infection. Most times this is not the case, but it must be ruled out and is not something that can wait until morning.
As for Tylenol™ and Motrin™, I do not recommend that she use either of these medications in the first 3 months of life unless directed by her physician. Often times the only sign small babies have when they are ill is fever. If she routinely uses either of these medications she may “mask” this early sign that something is not right.
Thus, in this scenario, the best answer is C.
Hope
Hope is a 2 1/2 year old previously healthy little girl. She is normally full of energy and very rambunctious. She attends daycare 3 days a week and loves to play outside during the summer. Over the last several days Hope has been having nasal congestion and a runny nose. She has an occasional cough throughout the day which seems worse at night-time. Although she is coughing some through the day she is not having any trouble breathing even though she does seem to be breathing a little more rapidly than normal.
She is not eating as much as normal and seems to prefer juice and clear liquids to milk. She did not sleep well last night on account of coughing and of course neither did either of her parents. Overall she is more “clingy” and fussy than normal. However she does not complain that anything hurts. Although she is not going to the bathroom as much as normal she has already urinated once this morning.
She feels warm so her mother measures her temperature using an ear thermometer and it reads 101.3 degrees F.
What should Hope’s mom do now?
A. Rush her to the ER, she could have pneumonia or meningitis.
B. Call her pediatrician immediately to schedule an appointment to check for ear infection.
C. Give her Tylenol™ or Motrin™ to bring the fever down.
D. Continue to encourage fluid intake, give her plenty of rest, and watch closely for the development of any more worrisome signs.
This is a classic presentation for a child with fever. I probably see 5-10 patients just like this every day. There are many important aspects of this story. Hope attends daycare, has congestion, runny nose, and a mild fever. This is all consistent with a viral illness – most likely a “cold.” She does not feel well but is not showing any of the the more worrisome signs of serious illness like difficulty breathing, lethargy, or severe pain. She is continuing to drink fluids and is still making some urine, all suggesting that there are no concerns for dehydration right now.
Her fever is less than 102°F and she does not seem to be terribly bothered by the fever. In this case it is better to leave the fever alone and this will allow her to fight off the “cold” much quicker. If on the other hand Hope is:
A. Refusing to drink fluids
B. Unable to go to sleep
C. In pain
D. Having difficulty breathing… OR
E. Lethargic
Then a trial of a fever reducer might be indicated. Remember though that fever reducers generally prolong the overall duration of illness, so avoid them if possible.
Although Hope is breathing rapidly, she is not having difficulty breathing, which is a symptoms of pneumonia. If Hope’s mom is concerned that her rapid breathing is an early sign of pneumonia, then she could give one dose of a fever reducer. If the rapid breathing resolves when the fever comes down then pneumonia has effectively been ruled out.
Children with meningitis are very sick… high fever, difficult to arouse, severe headache or neck stiffness, vomiting, unable to eat or drink, etc. Hope does not have any of these more worrisome symptoms.
As for ear infections, 4 out of 5 will resolve on their own without any intervention. If Hope is not in pain, does not have drainage coming from her ear, or any of the more worrisome sign of ear infection, then she does not need to be “checked” for ear infection. Most kids that have a “cold” along with congestion will have some fluid in their ears. This fluid does not equal infection. If Hope’s mom takes her in with these symptoms many doctors will feel compelled to “do” something and you will often prescribe an antibiotic. This is not only unnecessary but also exposes Hope to the risks of antibiotics and also promotes antibiotic resistant bacteria.
Thus, in this scenario, the best answer is D.
Kaden
Kaden is a 9-month old infant. His mom breast fed him up until he was about 4 months old. His mom, who is a teacher, had to return to work at the end of the summer and found it too difficult to pump at work to maintain her milk supply. Since this time he has been on formula, rice cereal and a few baby foods. Kaden also started attending daycare about this same time.
Up until 4 months, Kaden never had any problems at all. However, it seems that he has been sick constantly since his 4-month birthday. On most days it seems Kaden has all or some combination of runny nose, nasal congestion, or cough. Today he has been extra irritable and his mom decided to take off work to stay at home with him.
He is much more fussy than normal and did not sleep well at all last night. He is normally a very good feeder but today he only takes about 1 ounce of formula at a time and is not interested in eating any thing else at all. He has occasional coughing fits, especially when he lays down, and sometimes he even coughs so much that he throws up. He is not having any diarrhea or acting like he is in any severe pain, although his mom is concerned that he seems to be pulling at one of his ears.
When he wakes up from his afternoon nap, he is “burning up,” and his hands and feet are very cold. He seems to be breathing pretty rapidly and his breathing is very “raspy.” His mom gets very concerned and immediately checks his temperature under his arm which reads – 104.5 degrees F.
What should Kaden’s mom do next?
A. Rush him to the ER he probably has pneumonia.
B. Call the pediatrician, he probably has an ear infection.
C. Plan a trip to ER for IV fluids, he is probably dehydrated.
D. Give him a dose of fever reducer and reevaluate in about an hour.
This is a common scenario and has many great teaching points. First, we should deal with the fever and address whether or not it is concerning. Remember it is not the actual number that concerns us so much as the associated symptoms. The worrisome symptoms are:
A. Your child is refusing to drink fluids.
B. Your child is unable to go to sleep.
C. You child is in pain.
D. Your child is breathing rapidly.
E. Your child is lethargic.
In the scenario above Kaden is “breathing rapidly.” In the setting a fever, this could be worrisome for pneumonia, dehydration, or some other more serious infection. However, this is also the normal response to having a fever. All children, when they have a fever will breath rapidly, but that breathing should not be labored. The best way to distinguish between rapid breathing related to a fever, and rapid breathing related to something more serious is to give a trial of a fever reducer. If the breathing slows and Kaden looks great, then his mom will have effectively rule out a serious disease like pneumonia. This is what we often do in the ER.
Kids come in all the time with fever. In the short time I have to see kids it is often difficult for me to assess how sick they are when they have a high fever. So we often have the nurses give kids with high fever a dose of Tylenol™ or Motrin™ in the waiting room. Once they get back to see us, the fever is usually gone, and so are the other worrisome symptoms. If this is the case, then I feel very comfortable letting them go home and confident that something more serious is not going on. You can give kids with more serious illness all the Tylenol™ and Motrin™ you want and it will not make them any better.
In this case Kaden probably has a viral illness like the Flu. Especially now that he is no longer breastfed and he is going to daycare. For many parents there is no way to avoid taking your children to daycare. However, if your child spends any amount of time at daycare they will likely be sick often during the first two years of life. This is because toddlers and infants are not very good about keeping their germs to themselves. More, they are usually at daycare and contagious for a day or two before they get the high fever that keeps them out of daycare. Thus most daycare settings, in addition to caring for your child, are a great place for kids to swap their various illnesses. The good news is that most serious illnesses in this country are not very contagious… the contagious ones are the minor illnesses like colds and flus.
As for the other answers… Pneumonia is a rare problem in this country but potentially serious. If Kaden has pneumonia a trial of a fever reducer will not improve his rapid breathing and his breathing will likely be labored. If this is the case, his mom should notify her pediatrician right away.
An ear infection is a possibility. Read my page on ear pain for more information. You will note that most ear infections resolve on their own and can be treated at home with simple Home Remedies. If Kaden’s mom is suspicious for an ear infection she should try these before seeing her pediatrician.
In the absence of vomiting and diarrhea it is uncommon for children over 6 months of age to become dehydrated. If Kaden’s mom is worried about dehydration then she should consider supplementing his formula with some pedialyte. Often times it is too much work to take formula when kids have a stuffy nose and do not feel well. Pedialyte is much easier to take and most kids will stay hydrated as long as they are taking some fluids, even if they are not taking the normal amount. If Kaden will not take any fluids for more than 24 hours, then a call to the pediatrician is warranted to have him evaluated for dehydration.
Thus, in this scenario, the best answer is D.
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Dear Dr. Reynolds, I have baby boy who is 2yrs & 7 months old & is infected by bacteria with a fever running as high as 39.4 in the afternoon & that is going into the 4th day already. However, he seems ok & playful all the time. I don’t know if I should take him to his doctor or continue to let his immune system deal with the infection? Thank you Doctor.
Most bacterial (as opposed to viral) infections require antibiotic treatment to resolve. I can only speak in generic terms on this blog. You will have to consult with your pediatrician regarding the specifics of your child’s fever and infection. Again though (in generic terms) I would suggest antibiotic treatment for documented bacterial infections.
Im a nurse and all I want to say is finally!! Finally a Doctor with intelligence, integrity, and the guts to say what’s right!! We need more like you. Thank you so much for this site, it was a breath of fresh air!!!