Paracetamol as a risk factor for allergic disorders/Authors' reply

• Published in: The Lancet (British edition) Vol. 373; no. 9658; p. 119
• Main Authors: Singh, Meharban, Lawrence, J, Moore, E, Port, L, Danchin, M, Connell, T, Lowe, Adrian, Abramson, Michael, Dharmage, Shyamali, Allen, Katrina, Beasley, Richard, Clayton, Tadd, Crane, Julian, von Mutius, Erika, Lai, Christopher K W, Lawyer, Allison B
• Format: Journal Article
• Language: English
• Published: London Elsevier Limited 10.01.2009
• Subjects: Apoptosis; Asthma; Chemicals; Eczema; Molecular weight; Mortality
• ISSN: 0140-6736; 1474-547X

With this cross-sectional, retrospective study, Beasley and colleagues contend with the intrinsic difficulties of recall bias, misclassification bias, and confounding by indication.2 Paracetamol use has been found to be highly associated with an increased risk of all causes of death,3 highlighting the potential for drawing invalid conclusions about causal relations in observational studies of commonly used drugs. Among the more than 250 known causes2 of occupational asthma are organic compounds of low molecular weight with bifunctional reactivity composed of at least two basic, hydroxyl, carboxyl, sulfonyl, isocyanate, or similar reactive groups.3 Paracetamol has a molecular mass of 151 Da and features an acetamide group with a hydroxyl group on the opposite side of the molecule. Paracetamol's toxic effects on the liver are associated with increased concentrations of tumour necrosis factor and other cytokines that predict necrosisof cells.5 Paracetamolinduced apoptosis of cells in the airways might produce permanent changes in airway cell populations and explain the presence of asthma several years after paracetamol exposure.