Doxiflo 200 mg Tablet contains Doxofylline, a novel bronchodilator structurally distinct from Theophylline due to the presence of a dioxolane group. It selectively inhibits phosphodiesterase 4, leading to relaxation of bronchial smooth muscle. Unlike Theophylline, Doxofylline has decreased affinities toward adenosine A1 and A2 receptors, potentially accounting for its improved safety profile. Additionally, it inhibits platelet-activating factor (PAF) and the generation of leukotrienes.