Antipyretics cause the hypothalamus to override an interleukin-induced increase in temperature. The body will then work to lower the temperature and the result is a reduction in fever.
Most are also used for other purposes. For example, the most common antipyretics in the United States are aspirin and acetaminophen, which are used primarily as pain relievers. There is some debate over the appropriate use of such medications: fever is part of the body's immune response to infection.
Herbal remedies with a fever-reducing effect are called febrifuges, and include catnip, chamomile, sage and yarrow. However, the term febrifuge can also refer to a refrigerant, such as topical alcohol, which cools the body by physically removing heat rather than modifying the body's responses.