Antipyretics (/ænti.paɪˈrɛ.tɪks/, from anti- 'against' and 'feverish') are substances that reduce fever. Antipyretics cause the hypothalamus to override a prostaglandin-induced increase in temperature. The body then works to lower the temperature, which results in a reduction in fever.
Most antipyretic medications have other purposes. The most common antipyretics in the United States are ibuprofen and aspirin, which are non-steroidal anti-inflammatory drugs (NSAIDs) used primarily as analgesics (pain relievers), but which also have antipyretic properties; and acetaminophen (paracetamol), an analgesic with weak anti-inflammatory properties.
There is some debate over the appropriate use of such medications, as fever is part of the body's immune response to infection. A study published by the Royal Society claims fever suppression causes at least 1% more influenza cases of death, which would result in at least 700 extra deaths per year in the United States alone.
Bathing or sponging with lukewarm or cool water can effectively reduce body temperature in those with heat illness, but not usually in those with fever. The use of alcohol baths is not an appropriate cooling method, because there have been reported adverse events associated with systemic absorption of alcohol.