Antipyretic

Antipyretic refers to a pharmacological category of agents used to reduce elevated body temperature, commonly known as fever or pyrexia. Fever is a complex physiological response typically triggered by exogenous or endogenous pyrogens that induce the production of Prostaglandin E2 (PGE2) via the cyclooxygenase (COX) enzyme pathway. Once synthesized, PGE2 acts on specific EP3 receptors in the preoptic area of the hypothalamus to elevate the body's thermoregulatory set point, initiating heat-generating and heat-conserving mechanisms. Most antipyretic drugs, such as acetaminophen (paracetamol) and nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or aspirin, exert their effects by inhibiting COX enzymes, thereby blocking the synthesis of PGE2 and allowing the hypothalamic thermostat to return to its baseline. While highly effective for symptomatic relief, these agents must be used with caution due to risks such as gastrointestinal irritation, renal toxicity, and potential hepatotoxicity in the event of overdose.

Other names

AntifebrileFebrifugeAntipyretic agentFever reducer

Antipyretics function primarily by inhibiting the cyclooxygenase (COX-1 and COX-2) enzymes, which are responsible for converting arachidonic acid into Prostaglandin E2 (PGE2) [StatPearls: Antipyretic Medications]. Reduction of PGE2 in the central nervous system prevents the activation of prostaglandin E receptor 3 (EP3) in the preoptic area of the hypothalamus, which otherwise raises the body's thermoregulatory set point during a febrile response [PubMed: 11213233]. By lowering this set point, these agents facilitate heat loss through physiological mechanisms such as peripheral vasodilation and diaphoresis (sweating) [PubMed: 22100414].