Paracetamol (Acetaminophen) is a commonly used analgesic and antipyretic agent. It acts by preferentially inhibiting Cox-3 receptors. Angioedema to paracetamol is rare and likely to occur in children. Angioedema is a localized self-limiting swelling in the dermis, lip mucosa and tongue. It occurs due to release of plasma and vasoactive mediators.
Angioedema is generally subdivided into idiopathic angioedema, extrinsic factor induced angioedema and angioedema with C1-INH defciency. The extrinsic factor induced angioedema includes angioedema associated with Non Steroidal Anti Inﬂammatory Drug (NSAID) such as aspirin, paracetamol.
Generally NSAID-induced angioedema considered as a non-allergic reaction. The pathogenesis of NSAID induced angioedema is by inhibition of Cyclooxygenase (Cox) which results in signifcant
changes in arachidonic acid metabolism such as cysteinyl leukotriene excessive production. Recent research suggests that bradykinin play a vital role in the pathogenesis of most forms of nonallergic angioedema.
Patient with oropharyngeal angioedema may present with acute upper airway obstruction and this should be monitored for airway. Since, oedema from the site typically progresses rapidly and may end up in life-threatening complications
The important step in treatment of angioedema is to terminate the drug that suspected to trigger angioedema. Antihistamines and glucocorticoids often act as mainstay drugs in treatment of drug induced angioedema
All healthcare professionals should be aware of such a possibility of allergy due to paracetamol . Furthermore, such an event should be recognized early and treated accordingly.