Fever in Adults     

For good health, the body works best at a temperature of about 97 to 99 degrees F. Although body temperature rises slightly during the day, this change is not important unless your temperature is over 100.4 degrees F. In fact, many people have a temperature that is always a little above or below the 98.6 degrees F that is considered normal. A fever is defined as having a temperature over 99.6 degrees F orally, 98.6 degrees F under the armpit or 100.4 degrees F rectally. Body temperature may rise dramatically during vigorous physical activity such as running but drops quickly to normal when the activity is stopped.

Causes

Your body's temperature is an important indication of how well you are dealing with germs, stress, exertion or extreme changes in weather. By itself, a high temperature is not necessarily cause for concern. It can actually be a perfectly normal way for your body to defend itself against infection. Your body shivers to help produce the heat it needs to fight germs and sweats to regulate the rise in temperature.

Symptoms

These are symptoms of a fever:

• A feeling of chilliness or the shivers

• Shaking chills (rigors)

• Profuse sweating as the fever “breaks” 

• Aches

Self-Care

A fever is a special cause for concern in infants under 3 months of age, the elderly, and individuals who are taking medications that suppress the immune system. But for most people, there is no medical reason to try to reduce a fever unless it is accompanied by other symptoms of illness.

• With no other symptoms, medications are not necessary. But if fever makes you uncomfortable, take aspirin, acetaminophen (Tylenol or a generic) or ibuprofen (Advil or a generic). For children, use acetaminophen, not aspirin.

• Drink eight glasses of fluids a day. When you have a fever, you lose more body fluids than normal, so it's important to prevent dehydration.

• Call your doctor if fever lasts longer than three days or if you develop other symptoms.