Fever is a very common symptom of illness all through infancy and childhood. Young children are notorious for having high fevers with minor viral illnesses more often than adults do; the reason for this is not known, but it is true. Temperature may be measured under the arm (axillary) or rectally in infants under six months of age with essentially equivalent results. Beyond six months, one can start with an axillary reading; if the temperature is not over 101 degrees Fahrenheit in a child who feels very warm, this reading should be confirmed with a rectal temperature as there is a possibility for there to be a significant gap between surface temperature and rectal temperature in infants older than six months of age. Ear thermometers should be adjusted to the “rectal” setting; if there seems to be a discrepancy between the ear reading and how warm the baby feels, reconfirm the reading with a mercury thermometer.These thermometers can give erratic readings due to the fact that it may be difficult to aim the sensor directly at the tympanic membrane or from interference from ear wax in the external ear canal.

The newest technology is the temporal artery thermometers which read a core temperature analogous to the rectal temperature.Using the above guidelines, the normal temperature range is 97 to 100 degrees Fahrenheit. Fever is defined as a temperature greater than 101 degrees Fahrenheit measured as previously noted. The range from 100 degrees Fahrenheit to 101 degrees Fahrenheit is a “gray” or intermediate zone that must be interpreted in the light of the child’s overall condition.

Fever is not dangerous in and of itself, but is rather a symptom of an illness. The height of the fever does not correlate directly with the seriousness of the underlying illness. Infants and toddlers may have very high fever (104 degrees F- 106 degrees F) with self-limited, minor viral illnesses and may have a serious bacterial infection in need of urgent diagnosis and antibiotic therapy with a fever in the 101-102 degrees F range. It is also true that some children have convulsions with fever, but it is not true that the occurrence of convulsions correlates with the peak of the fever; most authorities believe that seizures are triggered by a rapid rate of temperature change. Thus, febrile convulsions often occur at the onset of an illness as the temperature rises very abruptly; often before the parent is aware that the child is ill.

Infants and children are often irritable when they have a fever due to the discomfort caused by the fever as well as the underlying illness (stuffy nose, sore throat, etc.). As the temperature is rising, they will feel chilly and may have shivers or chills; their hands and feet may be bluish and their extremities mottled. The body produces fever by contracting the circulation in the extremities and preventing the normal radiation of body heat to the outside; as core temperature is retained, the temperature rises. When the fever peaks, the blood vessels dilate giving the skin a red, flushed appearance and the patient feels hot and often breaks into a sweat as the temperature cycles down. Most childrens’ fevers are an accentuation of the normal daily variation in body temperature, being highest in the afternoon and evening and lowest in the early morning hours. Fever due to infections will not rise endlessly; in a neurologically normal person they will peak at ~ 106 degrees F or less and cycle downward without doing damage to the patient. The one exception to this is fever due to heat stroke; in this condition core temperature can rise above 106 degrees F and unless external cooling measures are taken, can do the patient great harm.

As it is true that fever is only a symptom of an underlying illness and will not do the patient harm and that febrile convulsions usually occur before the parent is aware that the child is ill, it follows that the only reason to treat the fever is to relieve the discomfort associated with the fever. When dealing with a febrile infant or child it is much more important to assess the nature and severity of the underlying illness. If a child is alert, making eye contact, is consolable in the parent’s arms and is able to take fluids it is likely that the child has a mild illness for which symptomatic therapy is all that is necessary initially. When children are ill, they often change their appearance and behavior rapidly. Thus, this child may have periods of increased irritability, decreased fluid intake and inconsolability. As long as these periods are intermingled with more normal behaviors, you are still likely to need to offer only symptomatic treatment. This treatment should be offered through the night to make the child more comfortable. In infants under 2-3 years of age, parents often feel better having an office visit the next day to determine the exact cause of the underlying illness (often a viral illness that will be resolved by the child’s immune system). As your child gets older and you gain more experience you will feel more comfortable “riding” these illnesses out for a few days and scheduling an office visit only when unusual symptoms occur or when significant fever persists beyond 1-2 days.

Danger signs that should prompt you to call our office regardless of the height of the fever include: extreme and persistent irritability; disorientation; prolonged inconsolability; bulging fontanel (soft spot); stiff neck; persistently rapid breathing; persistently blue or mottled skin color; prolonged decreased fluid intake and/or signs of dehydration; pinpoint red skin rash which does not “blanche” (disappear) when the skin is pulled taut.

Fever can be treated with acetminophen (Tylenol, Tempra, Panadol-4 hour intervals) or ibuprofen (Advil, Motrin-6-8 hour intervals; not to be used under 6 months of age). Acetaminophen is also available for the vomiting patient by suppository (Fever-All). The use of a combination of acetaminiphen and ibuprofen in a variety of alternating regimens has become a popular practice of both parents and practitioners. Yet, no conclusive proof indicates that alternating antipyretics is either safe or more efficacious than single drug therapy.Furthermore, alternating antipyretics may be confusing to parents and has the potential for incorrect dosing and increased risk of toxicity. Specifically, ibuprofen inhibits the production of glutathione that, in the presence of increased acetaminophen concentrations, can lead to liver or kidney toxicity in a febrile child who may be somewhat dehydrated. Therefore, in the absence of further data, parents should not use this combination approach and use only 1 antipyretic at the proper dosage and interval. (Pediatrics in Review 30:No.1; January, 2009). In patients older than 6 months of age and where taste is not an issue, ibuprofen has been shown to be more pain relieving and fever reducing than acetaminophen An alternative treatment is to give the child a sponge bath in lukewarm water. Make the water initially warm enough to avoid shivering. As the water cools gradually to room temperature, it will cool the child by evaporation. Do not add rubbing alcohol to the water as it may be absorbed and also cause chilling. Offer as much fluid as the child will take to provide the extra fluid and calories required due to the increased metabolic rate caused by the fever.

The dose of acetaminophen and ibuprophen is based on the child’s weight. We will write your child’s dosage on your take home summary sheet at each of your child’s check-ups. Please keep this information handy so that you can find it in the middle of the night.

Click here for approximate doses of acetaminophen and ibuprophen based on weight

In older children who prefer chewable Tylenol tablets, one chewable tablet is 80 mg and is equivalent to one dropperful of infant drops and one half tsp. of Tylenol liquid. The Advil/Motrin chewables come as 50 mg and 100 mg strengths and are equivalent to one half of one tsp. respectively.