Fever in Infants and Children

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How Do I Know If My Child Has A Fever?

What is a normal temperature?

A normal temperature is about 98.6°F (37°C) when taken orally (in your child’s mouth) and 99.6°F (37.5°C) when taken rectally (in your child’s bottom). Many doctors define a fever as an oral temperature above 99.5°F (37.5°C) or a rectal temperature above 100.4°F (38°C).

How should I take my child’s temperature?

You can get the most accurate temperature by taking his or her temperature rectally. But in a child older than 3 months of age, it’s fine to take it orally unless your doctor directs otherwise. Use a digital thermometer. Do not use a mercury thermometer. Mercury is an environmental toxin (poison), and you don’t want to risk exposing your family to it.

  • Be sure to label your rectal thermometer so that it isn’t accidentally used in your child’s mouth.
  • Before taking your child’s temperature, clean the thermometer in lukewarm soapy water and rinse it well with cool water.
  • If you’re taking your child’s temperature orally, wait at least 20 minutes after your child finishes eating or drinking hot or cold foods and beverages to take his or her temperature.
  • Don’t bundle your baby or child up too tightly before taking his or her temperature.
  • Don’t take your child’s temperature right after he or she has had a bath.
  • Never leave your child alone while using a thermometer.
  • After you’re done using a thermometer, clean it with rubbing alcohol or wash it in cool, soapy water.

Taking your child’s temperature rectally

If you’re taking your child’s temperature rectally, place him or her belly-down across your lap. Coat the tip of the thermometer with petroleum jelly (brand name: Vaseline) and insert it half an inch into the rectum. Stop if you feel any resistance. Hold the thermometer still and do not let go. When the thermometer beeps, remove it and check the digital reading.

Taking your child’s temperature orally

If you’re taking your child’s temperature orally, place the end of the thermometer under his or her tongue, towards the back of the mouth. Have your child close his or her lips on the thermometer. Tell your child not to bite down or talk. When the thermometer beeps, remove it and check the digital reading.

When Should I Call My Doctor?


If your child has any of the following warning signs, call your family doctor right away.

  • Constant vomiting or diarrhea
  • Dry mouth
  • Earache or pulling at ears
  • Fever comes and goes over several days
  • High-pitched crying
  • Irritability
  • No appetite
  • Pale appearance
  • Seizures
  • Severe headache
  • Skin rash
  • Sore or swollen joints
  • Sore throat
  • Stiff neck
  • Stomach pain
  • Swelling of the soft spot on an infant’s head
  • Unresponsiveness or limpness
  • Wheezing or problems breathing
  • Whimpering

If your child is:

Younger than 3 months of age, call your doctor right away if your baby’s rectal temperature is 100.4°F (38°C) or higher. Call your doctor even if your child doesn’t seem sick. Babies this young can get very sick quickly.

Three months of age to 6 months of age, call your doctor if your baby has a temperature of 102°F (38.8°C) or higher, even if your baby doesn’t seem sick.

Six months of age and older and has a fever of 102°F (38.8°C) to 102.9°F (39.4°C), watch how he or she acts. Call your doctor if the fever rises or lasts for more than 2 days.

Six months of age and older and has a fever of 103°F (39.4°C) or higher, call your doctor even if your child seems to feel fine.

How Can I Treat My Child’s Fever?

Should I try to lower my child’s fever?

Fevers are a sign that the body is fighting germs that cause infection. If your child is between 3 months of age and 3 years of age and has a low-grade fever (up to 102°F [38.8°C]), you may want to avoid giving him or her medicine. If your child is achy and fussy, and his or her temperature is above 102°F (38.8°C), you may want to give him or her some medicine.

If your baby is younger than 3 months of age and has a rectal temperature of 100.4°F (38°C) or higher, call the doctor or go to the emergency room right away. A fever can be a sign of a serious infection in young babies.

What kind of medicine should I give my child, and how much?

Do not give any medicine to babies who are younger than 2 months of age without talking to your doctor first.

Acetaminophen (one brand name: Children’s or Infants’ Tylenol) relieves pain and lowers fever. Check the package label or ask your doctor about the correct dosage for your child. The correct dosage depends on your child’s weight and age.

Ibuprofen is another medicine that can be used to lower a fever in children older than 6 months of age. Talk to your doctor before giving ibuprofen (two brand names: Children’s Advil, Children’s Motrin) to your child. Your doctor will tell you the correct dose for your child.

Can I give my child aspirin to lower his or her fever?

No. In rare cases, aspirin can cause Reye’s syndrome in children. Reye’s syndrome is a serious illness that can lead to death. Doctors recommend that parents should not give aspirin to children younger than 18 years of age.

What else can I do to help my child feel better?

  • Give your child plenty of fluids to drink to prevent dehydration (not enough fluid in the body) and help the body cool itself. Water, clear soups, popsicles and flavored gelatin are good choices.
  • If your child is getting enough fluids, don’t force him or her to eat if he or she doesn’t feel like it.
  • Make sure your child gets plenty of rest.
  • Keep the room temperature at about 70°F to 74°F.
  • Dress your child in light cotton pajamas. Overdressing can trap body heat and cause your child’s temperature to rise.
  • If your child has chills, give him or her an extra blanket. Remove it when the chills stop.

Will a bath help lower my child’s fever?

Giving your child acetaminophen and a lukewarm bath may help lower his or her fever. Give the acetaminophen before the bath. If the bath is given without medicine, your child may start shivering as his or her body tries to raise its temperature again. This may make your child feel worse. Never use rubbing alcohol or cold water for baths.

Tips on giving medicine

  • Don’t give more than 5 doses in 1 day.
  • Don’t give a baby younger than 2 months of age any medicine unless your doctor tells you to.
  • Read package labels carefully. Make sure you are giving your child the right amount of medicine.
  • For liquid medicines, use a special liquid measuring device to be sure you give the right dose. Get one at your drug store or ask your pharmacist. An ordinary kitchen teaspoon may not hold the right amount of medicine.

More Things To Consider

Questions to Ask Your Doctor

  • Is there any medicine I can give my child?
  • What is the correct dose of medicine for my child?
  • If my child’s fever goes up suddenly, should I take him/her to the emergency room?
  • How long should I wait to call the doctor if my child’s fever doesn’t go away?
  • What is the easiest way to take my child’s temperature?
  • How can I make my child comfortable during the fever?