Asthma, also known as chronic obstructive asthma, is related to allergic asthma and childhood-onset asthma, and has symptoms including recurring periods of wheezing, chest tightness and shortness of breath. An important gene associated with Asthma is IL13 (Interleukin 13), and among its related pathways/superpathways are Allograft rejection and Interleukin-4 and Interleukin-13 signaling. The drugs Dexmedetomidine and Fentanyl have been mentioned in the context of this disorder. Affiliated tissues include Lung and smooth muscle, and related phenotypes are asthma and bronchoconstriction