Fever, also known as pyrexia, is a temporary increase in body temperature that occurs as a response to an underlying illness or infection. It is one of the body’s natural defense mechanisms to help combat infections and promote healing. The normal body temperature for most individuals ranges between 97.8°F (36.5°C) and 99°F (37.2°C) when measured orally.
Fever occurs when the body’s internal thermostat, located in the hypothalamus of the brain, is reset to a higher temperature in response to infections or other inflammatory processes. This higher temperature helps to enhance the immune response and inhibit the growth of certain bacteria and viruses, making it more difficult for them to replicate.
Related Glossary Terms
- Hyperthermia: A condition where the body temperature rises significantly above the normal range, often due to excessive heat exposure or physical exertion, rather than as a result of an infection.
- Febrile: A term used to describe a person who has a fever.
- Afebrile: A term used to describe a person who does not have a fever.
- Antipyretics: Medications, such as acetaminophen (paracetamol) or ibuprofen, used to lower fever and reduce discomfort.
- Febrile Seizures: Convulsions that can occur in some children as a result of a sudden spike in body temperature during a fever.
- Chill: The sensation of feeling cold or shivering that may accompany the early stages of a fever.
- Sweating: The body’s response to a fever breaking, causing the skin to feel warm and sweaty as the temperature begins to return to normal.
- Remittent Fever: A fever that fluctuates but does not return to normal between spikes.
- Intermittent Fever: A fever that comes and goes at regular intervals.
- Continuous Fever: A fever that remains elevated without significant fluctuations.
It’s important to note that while fever itself is not an illness, it is often a symptom of an underlying condition, such as an infection (viral or bacterial), inflammatory disorders, or other medical conditions. In many cases, treating the underlying cause of the fever is essential for its resolution. However, mild fevers caused by common viral infections may not necessarily require treatment with antipyretics unless they cause significant discomfort or distress. If a fever is persistent, severe, or accompanied by other concerning symptoms, it’s crucial to seek medical attention for proper evaluation and management.