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Understanding Healthcare

Symptoms or Findings with Uncertain Cause (Child)

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Based on the exam and any tests that were done today, the exact cause of your child’s symptoms is not certain. Your child's condition does not seem serious, but the signs of a serious problem may take more time to appear. That's why it's important for you to watch for any new symptoms, or if your child’s condition gets worse. A repeat physical exam or more testing at a later time may reveal a cause for your child's symptoms that is not clear today. Follow up with your child's doctor or a specialist as directed today.


Home care

Your child can go back to their usual activities and diet when they feel able to do so, unless advised differently.


Follow-up care

Follow up with your child’s doctor or specialist, or as advised today. Contact the doctor sooner if your child's symptoms don't start to get better in the next few days.

If your child had any tests, such as an X-ray or ultrasound, the results will be reviewed by a specialist. You will be told of any new findings that may affect your child's care. Test results can be out of the normal range for a number of reasons. If today's tests were abnormal, it's important to follow up as advised.


When to get medical advice

Unless your child's doctor advises otherwise, call the doctor right away if any of the following occur:

  • Your child’s current symptoms get worse.

  • New symptoms appear.

  • Your child is not acting as they usually act.

  • Your child has a fever (see Fever and children, below).


Fever and children

Use a digital thermometer to check your child’s temperature. Don’t use a mercury thermometer. There are different kinds and uses of digital thermometers. They include:

  • Rectal. For children younger than 3 years, a rectal temperature is the most accurate.

  • Forehead (temporal). This works for children age 3 months and older. If a child under 3 months old has signs of illness, this can be used for a first pass. The doctor may want to confirm with a rectal temperature.

  • Ear (tympanic). Ear temperatures are accurate after 6 months of age, but not before.

  • Armpit (axillary). This is the least reliable but may be used for a first pass to check a child of any age with signs of illness. The doctor may want to confirm with a rectal temperature.

  • Mouth (oral). Don’t use a thermometer in your child’s mouth until they are at least 4 years old.

Use a rectal thermometer with care. Follow the product maker’s directions for correct use. Insert it gently. Label it and make sure it’s not used in the mouth. It may pass on germs from the stool. If you don’t feel OK using a rectal thermometer, ask the doctor what type to use instead. When you talk with any doctor about your child’s fever, tell them which type you used.

Below is when to call the doctor if your child has a fever. Your child’s doctor may give you different numbers. Follow their instructions.

When to call a doctor about your child’s fever

First, ask your child’s doctor how you should take the temperature.

For a baby under 3 months old:

  • Rectal or forehead: 100.4°F (38°C) or higher

  • Armpit: 99°F (37.2°C) or higher

  • A fever of ___________ as advised by the doctor

For a child age 3 months to 36 months (3 years):

  • Rectal or forehead: 102°F (38.9°C) or higher

  • Ear (only for use over age 6 months): 102°F (38.9°C) or higher

  • A fever of ___________ as advised by the doctor

In these cases:

  • Armpit temperature of 103°F (39.4°C) or higher in a child of any age

  • Temperature of 104°F (40°C) or higher in a child of any age

  • A fever of ___________ as advised by the doctor older

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© 2000-2025 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.
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