In IgE-mediated guinea pig asthma animal models, phenolic compounds extracted from Gastrodia (intervened at a dose of 12.5 mg/kg for 24 h) significantly inhibited the airway resistance in the acute and remission phases of asthma and effectively inhibited the recruitment of white blood cells, reduced histamine release, and inhibited eosinophil peroxidase (EPO) and phospholipase A activities. Here, EPO is linked to asthma.