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Today, doctors recommend that parents always use a digital thermometer to take their child's temperature.

Mercury thermometers are no longer used since mercury is a toxic metal. If you have a mercury thermometer, contact your local health department to learn how to safely remove it from your home.

Breakdown of Digital Thermometers

1. Rectal (in the bottom)

Age Guideline
Birth to 3 years

Pros and Cons
Rectal thermometers get very accurate readings. Parents worry about this technique, but there is little risk for injury if done correctly. However, make sure to label the thermometer as rectal so it is not also used orally.

How to Use
Clean the end of the thermometer with rubbing alcohol or soap and water. Use a small amount of lubricant on the end. Insert the thermometer ½ inch to 1 inch into the anus. Do not insert it too far. Keep it there for 1 minute, until you hear the beep.

2. Oral (in the mouth)

Age Guideline
4 to 5 years

Pros and Cons
You must wait 15 minutes after your child has had a cold or hot drink before using this technique.

How to Use
Clean the thermometer. Place the tip under your child's tongue toward the back of his mouth. Hold in place until you hear the beep.

3. Axillary (under the arm)

Age Guideline
Useful for screening at any age. Suggested for babies 3 months and older.

Pros and Cons
This technique is the least reliable for an accurate reading. But it is useful for screenings.

How to Use
Make sure there is no clothing  between your child's skin and thermometer. Place the disk in the armpit and bring the arm down against the chest wall so the disk is covered.

4. Side of forehead (temporal artery)

Age Guideline
3 months and older. Before 3 months, only useful as screening device

Pros and Cons
This thermometer is easy to use. It is as accurate as a rectal thermometer and causes less discomfort.

How to Use
Run the sensor across the forehead.

5. In the ear (Tympanic)

Age Guideline
6 months and older

Pros and Cons
This thermometer may be difficult to use at first but with practice it gets easier. Earwax may interfere with an accurate reading. It also may not give an accurate reading for newborns and older infants.

How to Use
Place the thermometer pointed toward the eardrum. It will take only a second to give a reading.

When to Call Your Healthcare Provider

As a parent, your intuition about your child's health and your observation of their appearance, mood and activity level are important components in deciding to call your healthcare provider. A fever is one symptom of illness, not the illness itself. Your child may be extremely ill and not have a fever or your child may have a high fever and be only mildly ill. Your decision to contact your doctor should be based on all of your observations, along with a temperature check. The exceptions to this are below.

Always call your healthcare provider if:

  • Your child doesn't easily awaken, looks very ill and is less responsive than normal
  • Your child has other symptoms such as earache, throat pain, seizure, trouble breathing, severe headache, stiff neck or decreased urination.
  • Your child is under 2 years old and has a fever that lasts more than 24 hours
  • Your child is 2 years or older and has a fever that lasts for 3 days or longer.

When you do call your child's healthcare provider, inform him or her of the reading of the thermometer and where the temperature was taken (ear, mouth, underarm, forehead or rectum). Also be prepared to inform your healthcare provider of any other symptoms your child may have. It's difficult to stay relaxed when your child may be ill, but try to listen and answer any questions as accurately as possible.

Guidelines for Fever Temperature

Call your healthcare provider if your child has a fever at these temperatures:

Infant under 3 months old:

  • Armpit temperature of 99°F (37.2°C) or higher.
  • Rectal or forehead temperature of 100.4°F (38°C) or higher.

Child age 3 to 36 months:

  • Armpit temperature of 101°F (38.3°C) or higher.
  • Rectal, forehead, or ear temperature of 102°F (38.9°C) or higher.

Child of any age:

  • Consistent temperature of 104°F (40°C) or higher.

How to Treat It

Fever fights infection as part of the body's natural immune response. However, since a fever may make your child fussy or uncomfortable you may wish to treat the fever with acetaminophen or ibuprofen.

Speak with your healthcare provider before giving medicine if your child is under 2 years of age. Follow the dosing instructions given to you by your healthcare provider.

Acetaminophen and ibuprofen will usually make your child's fever go down, but it may not return to a normal temperature. Sometimes a fever does not respond to medication, and this does not always mean your child is more seriously ill.  If your child's fever does come down, expect it to rise as the medicine wears off, in about 3 to 4 hours. You may need to give another dose, every 6 hours, or as instructed by your child's healthcare provider.

Before offering medicine, make sure your child is not dressed too warmly. Dress him or her in loose, comfortable clothing. A lukewarm bath may be soothing for your child. Avoid a cold bath, ice packs, or other methods of making your child cold. This can actually raise a temperature higher. Never use alcohol wipes or baths because alcohol may be absorbed through the skin and cause serious illness.

Fever itself it not dangerous, but it may cause dehydration. So encourage your child to drink lots of fluids.

If you have concerns about your child's fever, speak with your child's healthcare provider.

Matthew Weiland, DO

Methodist Physicians Clinic - HealthWest

Matt Weiland, DO enjoys family medicine and treating all the members of a family - from newborns to seniors. He like the variety of treatments he sees through treating patients of varying ages. As a doctor of osteopathy, Dr. Weiland has received special training in the musculoskeletal system, the body's interconnected system of nerves, muscles and bones. Dr. Weiland is an active sportsman. He enjoys mountain biking, water and snow skiing, golf and scuba diving. ...

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