Dai X, Dharmage SC, Abramson MJ, et al. - In the present study, the researchers sought to explore connections between early life acetaminophen use and adolescent asthma and lung function and to evaluate potential interactions by glutathione S-transferase (GST) polymorphisms. Usage of acetaminophen was reported 18 times until 2 years of age (n = 575 [92.7%]). Candidates were genotyped for GST polymorphisms ( GSTM1/T1/P1) (n = 429 [69.2%]). Asthma and lung function have been measured at 12 (n = 365 [58.9%]) and 18 years (n = 413 [66.6%]). Doubling of days of acetaminophen usage was correlated with decreased prebronchodilator FEV ₁/forced vital capacity and midexpiratory flow at age 18, however, this correlation was not observed when restricted for nonrespiratory purposes, suggesting confounding by indication. However, increased use of acetaminophen for nonrespiratory reasons has been associated with reduced FEV ₁ and midexpiratory flow at 18 years in children with GSTM1 null and GSTT1 present. Increased acetaminophen use was linked to asthma at 18 years for children with GSTP1 Ile/Ile, but not other GSTP1 genotypes. Such novel results need to be tested for consistency in other research, but indicate that children with risk genotypes may be vulnerable to acetaminophen use respiratory consequences.