By Dr. Kathleen Chin, M.D.
Common questions we hear from parents:
• Do I have to treat my child’s fever when he/she is acting fine?
• What fever reducer should I use, Acetaminophen (Tylenol) or Ibuprofen (Advil, Motrin)?
• Can I use them together or alternate them?
In medical books, fever is defined as a core body temperature of 100.5°F or higher. The average temperature of 98.6°F was described in 1876 based on the average temperature of healthy adults. However, if you measured a person’s core body temperature every hour for 24 hours, the temperature can range from as low as 96.7°F to 100.4°F depending on a person’s activity level as well as environmental temperature (a hot summer day).
The treatment of fever must be determined on a case-by-case basis based on your child’s medical history and discomfort level. An elevated body temperature in an otherwise healthy child, even as high as 105.8°F (41°C), typically poses no danger, persists briefly, and might benefit the child. It is important to remember that fever is a symptom, not a primary illness. No evidence suggests that the increase in temperature worsens the course of the illness or poses a risk of neurologic complications. The underlying illness, most commonly a viral infection, is responsible for the illness, not the fever.
What does a fever do for the body?
The main mechanism of fever, secondary to an infectious process, involves pyrogens. Pyrogens can be products of viral or bacterial factors or antigen-antibody complexes and your body’s natural immune defenses. These active products stimulate the release of inflammatory proteins that stimulate your immune system. They also stimulate increased production of prostaglandin E, which works in the part of the brain to reset the body’s thermostat to a higher level. Although this will cause temperature to rise, the body will also release other proteins as part of the immune system to provide feedback to prevent the temperatures from rising to dangerous levels.
In other words, “Fever is your friend” and can be beneficial. Certain components of the immune system can be enhanced during a fever, and some data supports that allowing the fever to continue will shorten the overall course of the illness. Fever hinders bacterial replication and enhances your white blood cell production to fight bacteria and viruses.
Treatment of fevers
The American Academy of Pediatrics (AAP) recommends reducing fever if needed to decrease discomfort. The emphasis should be on the level of comfort, not the level of the temperature. Careful observation of the child and ensuring adequate fluid intake are important. The risk of serious illness is more accurately predicted by the child’s clinical presentation rather than the height of the fever. Red flags for serious infection include dehydration, rapid or labored breathing, poor peripheral perfusion, and petechial rash.
Which should I choose?
The AAP has concluded that acetaminophen and ibuprofen have no significant difference in safety and efficacy. One minor difference is that ibuprofen has a longer duration of fever control, up to 8 hours. Acetaminophen has an effect that lasts between 4 and 6 hours. If a child has problems with gastritis or peptic ulcers, acetaminophen is safer. If a child has problems with liver function, ibuprofen is safer. Alternating regimens still is a popular custom however; the AAP has concluded that there is a lack of evidence for using alternating regimens, and that using them may result in increased dosing error or overdose. We advocate using another medication for fever control only if the one agent has not made the child more comfortable after 2 hours after the first agent.
Fever is a natural and a healthy response to infection and other physiologic insults. Aside from specific worrisome situations such as those described here, the fever usually will run a benign course.
When the decision is made to treat with antipyretics (Tylenol, Motrin or Advil), ensuring correct dosing and when to use them is imperative. Although alternating regimens using acetaminophen and ibuprofen lower temperatures more effectively than either agent alone, this practice may lead to increased dosing errors.