<prompt> Zafirlukast used in asthmatic patients acts byPhosphodiesterase inhibitionEndothelium receptor blockageLeukotriene receptor blockageLipoxygenase inhibitor  <response>: Drugs for Bronchial AsthmaMechanism of actionDrugsBronchodilators b2 sympathomimetics Salbutamol, Terbutaline, Bambuterol, Salmeterol, Formoterol, Ephedrine Methylxanthine Theophylline, Aminophylline, Choline theophyllineAnticholinergics Ipratropium bromide, Tiotropium bromide Leukotriene antagonist Montelukast, Zafirlukast Mast cell stabilizers Sodium cromoglycate, Ketotifen Coicosteroids Systemic Hydrocoisone, Prednisolone Inhalational Beclomethasone, Budesonide, Fluticasone, Flunisolide, Ciclesonide Anti IgE antibody Omalizumab Refer: Rang and Dales Clinical Pharmacology, 7th edition, pg no: 345 