PHENYTOIN-INDUCED ANAPHYLAXIS: A CASE REPORT

Anaphylaxis is a severe, life-threatening, systemic hypersensitivity reaction that occurs rapidly after exposure to an allergen. First described by Charles Richet and Paul Portier in 1902, the term "anaphylaxis" (from Greek: ana—against and phylaxis—protection) refers to an acute immune response that leads to systemic inflammation and potentially fatal complications [1]. It commonly occurs within minutes of exposure to triggers such as drugs (e.g., penicillin, NSAIDs), foods (e.g., peanuts, shellfish), and insect stings (e.g., bee or wasp venom), though it may also arise from idiopathic causes or exercise-induced factors [2]. The reaction is primarily mediated by immunoglobulin E (IgE), which binds to mast cells and basophils, leading to the rapid release of histamine and other inflammatory mediators [3]. This results in widespread vasodilation, increased vascular permeability, and bronchoconstriction, causing symptoms such as urticaria, angioedema, bronchospasm, hypotension, and anaphylactic shock [4]. Early recognition and immediate administration of intramuscular epinephrine are crucial in preventing fatal outcomes [5]