Fever in Adults
Welcome to this symptom guide about fever. Sorry to hear you have a fever!
This guide is intended for adults who have an abnormally elevated temperature. Although we think of normal body temperature as 98.6 degrees F, body temperature varies -- and so does the definition of fever. Since body temperature rarely climbs above 99.9 degrees without a reason, this guide will consider a fever to be present when the body temperature is 100.0 F (38 degrees C) or higher. While temperatures between 98.6 and 99.9 degrees might be high for you, minor elevations in temperature are less likely to be a true indication of illness and are often within the range of normal variation.
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