A practical guide from the physicians at Essential Pediatrics.
Fever is one of the most common reasons parents call a pediatrician, and one of the things they worry about most. In most children, a fever is a sign that the immune system is working as it should. Knowing when to watch, when to treat, and when to call makes it far easier to handle.
What is a fever?
A fever is a body temperature of 100.4°F (38°C) or higher. Anything below that is not a fever, even if your child feels warm.
Fever is a symptom, not a disease. It is the body’s normal response to infection, usually an ordinary virus such as a cold, the flu, or a stomach bug. The fever is not the illness; it is the body responding to one.
For infants, a rectal temperature is the most accurate. Older children can be checked with an oral, ear, or forehead thermometer, used according to the manufacturer’s instructions. A hand on the forehead can mislead, so use a thermometer to confirm.
Should I worry about the temperature?
The temperature itself is usually less important than how your child looks and behaves. Children with high fevers may have routine viral illnesses, while some serious infections cause only modest fevers.
To gauge how your child is really doing, ask:
- Are they alert, or hard to wake?
- Are they drinking fluids?
- Are they responding to you and able to be comforted?
- Are they breathing comfortably?
A child who is playful between doses of fever medicine is far less concerning than one with a lower temperature who is lethargic. Watch the child, not the number. Once you have confirmed a fever, there is no need to recheck it every twenty minutes.
How should I treat a fever at home?
The goal is comfort, not a normal thermometer reading. If your child is comfortable, drinking, and resting, treatment may not be needed at all.
Encourage fluids. Preventing dehydration is the most important part of home care. Small, frequent sips of water, breast milk, formula, or an electrolyte drink work well, and steady wet diapers are a good sign. Eating little for a day or two is fine. Fluids matter more than food while your child is sick.
Keep them comfortable. Light clothing and a comfortable room are better than heavy blankets, which trap heat. With young babies in particular, make sure your child isn’t simply overdressed or overheated.
Use medication for comfort. Acetaminophen (Tylenol), or ibuprofen (Motrin) for children 6 months and older, can help a child who feels miserable. Fever medicine can make your child more comfortable, but it does not treat the infection causing the fever, so it isn’t a sign of how serious the illness is. Dose by weight and follow the label, and use the syringe or cup that comes with the medicine rather than a kitchen spoon. Confirm the concentration printed on the label before dosing, since products can differ. Never give aspirin to a child, because of the risk of Reye’s syndrome. Do not wake a sleeping child to give a dose. If you are unsure of the right amount, call us.
Skip cold baths and alcohol rubs. They cause shivering, which raises the temperature and makes a sick child more uncomfortable.
When should I call my pediatrician?
Contact your pediatrician if your child:
- Is under 3 months old and has any fever of 100.4°F or higher
- Has a temperature of 104°F or higher
- Has a fever lasting more than 3 days, or fevers that keep returning
- Had a fever that went away for more than a day and then came back
- Has ear pain, a severe sore throat, pain with urination, or persistent vomiting
- Has a limp, is refusing to bear weight on a leg, or has a swollen joint
- Has redness or swelling around an eye
- Is drinking very little or making fewer wet diapers
- Developed a fever after recent international travel
- Has a weakened immune system or a significant underlying condition, such as heart disease, cancer, sickle cell disease, or an immune disorder
- Seems much sicker than you would expect
In many cases, a brief phone conversation is enough to determine whether your child can be safely cared for at home or should be evaluated in the office or emergency department.
A fever after a routine vaccination is common and usually passes within a day or two. Treat it for comfort as you would any fever, and call us if it is high, lasts longer than a couple of days, or your child seems unusually unwell.
For infants under 3 months, a fever is never a wait-and-see situation. Young babies can have serious infections with few outward signs, and a fever may be the only one. In fact, a young baby may have a serious infection with only a low temperature or none at all, so a change in feeding, alertness, fussiness, or color matters just as much. Call us right away, day or night, and we will guide you on what to do next.
When is a fever an emergency?
Seek care immediately if a fever comes with any of the following:
- Difficulty breathing, fast breathing, or working hard to breathe
- A stiff neck or a severe headache
- A rash of purple or blood-colored spots that does not fade when pressed
- A seizure
- Being very hard to wake, limp, or confused
- Signs of dehydration: no tears when crying, a dry mouth, or far fewer wet diapers
- A temperature that reaches 105°F (40.6°C)
A fever that lasts five days or more, even if your child otherwise seems well, should be evaluated. A prolonged fever can come from infections that need treatment, such as pneumonia, the flu, strep throat, or an ear infection, and the point of the visit is to find the cause.
Febrile seizures. Some children between 6 months and 5 years have a seizure triggered by fever. They are frightening to witness but usually brief and harmless, and do not mean a child has epilepsy. If one happens, lay your child on their side, away from hard objects, and put nothing in their mouth. Call 911 if it is their first seizure, lasts longer than five minutes, or your child does not recover quickly afterward. Any child should be examined after a first febrile seizure.
Common myths about fever
- Teething does not cause a true fever. A temperature of 100.4°F or higher deserves the same attention as any other fever.
- Ordinary fevers do not harm the brain. The body keeps infection-driven fevers within a safe range.
- Alternating Tylenol and Motrin is usually unnecessary. Some families are instructed to alternate in specific situations, but it increases the chance of a dosing error. Unless your pediatrician advises it, one medication used correctly is enough.
- A fever does not have to “break” for your child to recover. Fevers often rise and fall over the course of an illness, especially as medication wears off, and that pattern is normal. One exception is worth knowing: a fever that goes away completely for more than a day and then returns can signal a new infection, and is worth a call.
The bottom line
Most fevers are caused by common viral infections and resolve on their own. Rather than focusing on the number, watch how your child looks, acts, drinks, and breathes. When something seems wrong, trust your judgment and reach out.
At Essential Pediatrics, we limit each physician’s panel to a few hundred families, so your child’s doctor knows your child and is reachable when it matters. When a child develops a fever, timely access to your pediatrician can provide reassurance and help determine whether your child needs to be seen.
Frequently asked questions
What temperature counts as a fever? A fever is a body temperature of 100.4°F (38°C) or higher. Below that, your child may feel warm but does not have a fever.
My baby is under 3 months old and has a fever. What should I do? Call us right away, day or night. For babies under 3 months, any fever of 100.4°F or higher should always prompt a call rather than waiting, and we will guide you on what to do next.
Is a high fever dangerous on its own? For everyday illnesses, the height of the fever matters less than how your child looks and acts. The body keeps infection-driven fevers within a safe range. Call your pediatrician if you are worried.
Should I give Tylenol or Motrin? Either acetaminophen, or ibuprofen for children 6 months and older, can help a child who feels miserable. Dose by weight, follow the label, and never give aspirin. Alternating the two is rarely necessary unless your pediatrician advises it.
When is a child’s fever an emergency? Seek care right away if a fever comes with trouble breathing, a stiff neck or severe headache, a rash of purple spots that does not fade when pressed, a seizure, extreme sleepiness or confusion, signs of dehydration, or a temperature that reaches 105°F. Trust your instinct if something feels wrong.
Can teething cause a fever? Teething may make a baby slightly warm, but it does not cause a true fever. A temperature of 100.4°F or higher deserves the same attention as any other fever.
Is fever after a vaccine normal? Yes. A fever after a routine vaccination is common and usually passes within a day or two. Treat it for comfort as you would any fever, and call your pediatrician if it is high, lasts longer than a couple of days, or your child seems unusually unwell.
Does a fever need to break before my child recovers? No. Fevers often rise and fall over the course of an illness, especially as medication wears off, and that pattern is normal. One exception: a fever that goes away completely for more than a day and then returns can signal a new infection and is worth a call.
