Q. If I have a fever, at what temperature should I go to the doctor?

An oral temperature above 100 degrees Fahrenheit or a rectal or ear temperature above 101 F is considered a fever in the majority of adults.If your temperature reaches 103 F, you should contact a physician. Another alarm bell is a fever that lasts more than three days.In addition, get to a doctor immediately if you have a fever with any of the following: unrelenting vomiting, trouble breathing, a strong headache, confusion, pain when urinating, swollen throat, skin rash, sensitivity to light, stiff neck, chest pain, extreme listlessness or irritability and abdominal pain.A fever usually means your body is fighting an infection from bacteria or a virus. In older adults, the immune system doesn't function as efficiently as it does in younger people. The body's fever response to infection is not always automatic in elderly people. More than 20 percent of adults over age 65 who have serious bacterial infections do not have fevers.Body temperature fluctuates during the day between 97 F and 99 F. When you wake up, your temperature is at the low end of the range; it increases as the day progresses. The common standard for a "normal" temperature is 98.6 F. However, the range of normal is about a degree above or below 98.6.Use a high-quality thermometer to check your temperature. Thermometers today are high-tech electronic gizmos with beeps and digital readouts. Those mercury-filled glass thermometers are out because they are environmental hazards. Tympanic thermometers that get a quick read from the ear are good for older adults.Symptoms that can accompany fever include: headache, perspiration, shivering, aches, diminished appetite, dehydration and malaise. A fever higher than 103 F can cause seizures and hallucinations.If you get a fever, it's important to take in enough liquids to prevent dehydration.Physicians often recommend ibuprofen, acetaminophen or aspirin to lower a high fever.Taking medicine to lower a fever is especially important for older adults with heart conditions that might be affected by the stress of fever.But don't take any drugs without medical supervision. Over-the-counter medicines can be harmful if you take too much of them.If you have a fever below 102 F, medicine isn't usually recommended to lower your temperature. Low-grade fevers may be your body's way of fighting an infection. Take a tepid bath. Wear lightweight clothes.The views of the author do not necessarily state or reflect those of the Times News.