A case of maoto-induced interstitial pneumonia

Maoto (Ma Huang Tang in Chinese) is composed of four medical herbs (Ephedrae Herba, Cinnamomi Cortex, Armeniacae Semen and Glycyrrhizae Radix) and is traditionally prescribed for acute febrile diseases or upper respiratory tract infections (1,2). Clinical studies have shown that maoto improves flu symptoms with efficacy comparable to that of neuraminidase inhibitors in adults infected with the influenza A virus (3). Furthermore, maoto has shown clinical efficacy for seasonal influenza without severe adverse effects in randomized controlled trials (4). It is therefore considered a safe and efficient traditional drug for patients with flu like symptoms and is thus prescribed widely in eastern Asia. We herein demonstrate a case of maoto-induced interstitial pneumonia mimicking acute exacerbation of idiopathic pulmonary fibrosis (IPF). To our knowledge, no case reports of maoto-induced interstitial pneumonia have been published