pyrogen

biochemistry

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Last updated

July 13, 2026

Quick Summary

A pyrogen is a substance that produces fever. Fever is an abnormally high body temperature, often a sign of illness, but can also result from other factors like strenuous exercise or heat exhaustion.12

When the body encounters bacteria or viruses, the immune system can produce pyrogens. These substances travel to the brain and affect the hypothalamus, the body's temperature regulator. This causes the hypothalamus to raise the body's temperature, resulting in a fever. Elevated temperatures can help the body fight off infections by enhancing the function of white blood cells and antibodies, and may even directly inhibit the growth of some pathogens.2

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human disease
Disease: signs and symptoms
…protein and polysaccharide substances called pyrogens, released either from bacteria or viruses or from destroyed cells of the body, are capable of raising the thermostat and causing a rise in body temperature. Fever is a highly significant indicator of disease.
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…protein and polysaccharide substances called pyrogens, released either from bacteria or viruses or from destroyed cells of the body, are capable of raising the thermostat and causing a rise in body temperature. Fever is a highly significant indicator of disease.
Read More

fever
…system’s responses is to produce pyrogens. These chemicals are carried by the blood to the brain, where they disturb the functioning of the hypothalamus, the part of the brain that regulates body temperature. The pyrogens inhibit heat-sensing neurons and excite cold-sensing ones, and the altering of these temperature sensors deceives…
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…system’s responses is to produce pyrogens. These chemicals are carried by the blood to the brain, where they disturb the functioning of the hypothalamus, the part of the brain that regulates body temperature. The pyrogens inhibit heat-sensing neurons and excite cold-sensing ones, and the altering of these temperature sensors deceives…
Read More