This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Asthma, Subject name: Pharmacology
Mechanism of action of zeulton is? 
Select and explain. 
A. Inhibits production of IgE, B. Inhibits Lipoxygenase, C. Inhibits Cyclooxygenase, D. Inhibits activity of mast cells
B: Inhibits Lipoxygenase
Answer: B: Inhibits Lipoxygenase 
Explanation: ANSWER: (B) Inhibits LipoxygenaseREF: Goodman and Gillman s 11th ed page 479LEUKOTRIENE-SYNTHESIS INHIBITORS:The formation of leukotrienes depends on lip oxygenation of arachidonic acid by 5-lipoxygenase. Zileuton is a potent and selective inhibitor of 5-lipoxygenase activity and thus blocks the formation of all 5-lipoxygenase products. Thus, in addition to inhibiting the formation of the cys-LTs, zileuton also inhibits the formation of leukotriene B4 (LTB4), a potent chemotactic autacoidf and other eicosanoids that depend on leukotriene A4 (LTA4) synthesis.Logically, the therapeutic effects of a 5-lipoxygenase inhibitor would include all those observed with the CysLT-receptor antagonists, as well as other effects that may result from inhibiting the formation of LTB4 and other 5-lipoxygenase products.