Health: First Aid for Fever
Fever is one of your body's reactions to infection. What's normal for you may be a little higher or lower than the average temperature of 98.6 F (37 C). But a rectal temperature higher than 100.4 F (38.0 C)is always considered a fever. A rectal temperature reading is generally 1 degree Fahrenheit higher than an oral reading.
Don't treat fevers below 102 F (38.9 C) with any medications unless advised to do so by your doctor. If you have a fever of 102 F (38.9 C) or higher, your doctor may suggest taking over-the-counter medications such as acetaminophen (Tylenol, others) or ibuprofen (Advil, Motrin, others). Adults may also use aspirin. But don't give aspirin to children. It may trigger a rare, but potentially fatal, disorder known as Reye's syndrome. Also, don't give ibuprofen to infants younger than 6 months of age.
How to take a temperature
You can choose from several types of thermometers. Today most have digital readouts. Some take the temperature quickly from the ear canal and can be especially useful for young children and older adults. Other thermometers can be used rectally, orally or under the arm. If you use a digital thermometer, be sure to read the instructions, so you know what the beeps mean and when to read the thermometer. Under normal circumstances, temperatures tend to be highest around 4 p.m. and lowest around 4 a.m.
Because of the potential for mercury exposure or ingestion, glass mercury thermometers have been phased out and are no longer recommended.
Taking a rectal temperature is also an option for older adults when taking an oral temperature is not possible.
Orally
To take your temperature orally:
- Place the bulb under your tongue.
- Close your mouth for the recommended amount of time, usually three minutes.
- If you're using a nondigital thermometer, remove it from your mouth and rotate it slowly until you can read the temperature accurately.
Under the arm (axillary)
Although it's not the most accurate way to take a temperature, you can also use an oral thermometer for an armpit reading:
- Place the thermometer under your arm with your arm down.
- Hold your arms across your chest.
- Wait five minutes or as recommended by your thermometer's manufacturer. Then remove the thermometer and read the temperature.
- An axillary reading is generally 1 degree F less than an oral reading
Get medical help for a fever in these cases:
- If an adult has a temperature of more than 103 F (39.4 C) or has had a fever for more than three days.
- Call your doctor immediately if any of these signs or symptoms accompanies a fever:
- A severe headache
- Severe swelling of the throat
- Unusual skin rash
- Unusual eye sensitivity to bright light
- A stiff neck and pain when the head is bent forward
- Mental confusion
- Persistent vomiting
- Difficulty breathing or chest pain
- Extreme listlessness or irritability
- Abdominal pain or pain when urinating
- Any other unexplained symptoms
When reporting a fever to your doctor, don't attempt to convert from a rectal reading to an oral reading. It's simpler to just report what the reading was and how you took it.
For more first aid information, visit www.mayoclinic.com.