A plant-based compound using extracts of three herbs, dubbed the anti-asthma herbal medicine intervention (ASHMI), significantly improves lung function in patients with moderate to severe asthma. Moreover, the agent produces results comparable to those achieved with the steroid drug prednisone, according to researchers in the United States and China.

This is the first well-controlled study in which an anti-asthma Chinese herbal medicine has been found to be as effective as a corticosteroid drug,senior investigator Dr. Xiu-Min Li stated.

In the Journal of Allergy and Clinical Immunology, Li of Mount Sinai School of Medicine, New York and colleagues note that ASHMI has shown benefit in mouse studies of asthma. It is a simplified version of a 14-herb based traditional medication used to treat asthma in a Beijing hospital.

To investigate further, the researchers conducted a study with 91 patients who were randomly assigned to the oral ASHMI and a placebo or oral prednisone and a placebo.

At four weeks, lung function significantly improved in both groups. There was slight, but significantly greater improvement in the prednisone group.

In both groups, there was a significant and similar reduction in symptom scores, the need for beta-2 bronchodilator therapy and a blood marker of inflammation

Although both agents were almost equally effective in treating asthma, the investigators conclude, ASHMI had no negative effect on adrenal function.

Li added that additional clinical studies of ASHMI in the United Sates are planned. ASHMI may become an important addition to currently used drugs for asthma.