Fever

Fever is the elevation of core body temperature above the normal range, regulated by the hypothalamic thermoregulatory center[1]. It is a systemic response to exogenous pyrogens (such as pathogens) and endogenous pyrogens (notably cytokines including IL-1, IL-6, and TNF), which act on the hypothalamus to induce synthesis of prostaglandin E2 (PGE2). PGE2 then binds to EP3 receptors on neurons in the preoptic area (POA) of the hypothalamus, activating neural circuits that increase body temperature through heat generation (brown adipose tissue and shivering) and decreased heat loss (cutaneous vasoconstriction)[1][2][3][4]. Fever supports the body's defense against infection by enhancing immune cell function, but can also represent a metabolic stress.

Other names

PyrexiaFebrile response

Not directly applicable, but antipyretic drugs reduce fever primarily by inhibiting cyclooxygenase enzymes (COX-1, COX-2), thus reducing production of prostaglandin E2 (PGE2) in the hypothalamus, and lowering the hypothalamic set-point for body temperature[1][3].