Efficacy and mechanisms of action of traditional Chinese medicines for treating asthma and allergy

Background

Although corticosteroids and β₂-agonists are effective in managing asthma symptoms, a curative therapy for asthma is lacking. Traditional Chinese medicine (TCM), used in Asia for centuries, is beginning to play a role in Western health care as a complementary and alternative medicine modality. There is increasing scientific evidence supporting the use of TCM for asthma treatment.

Objective

This review article discusses promising TCM interventions for asthma and explores their possible mechanisms of action.

Methods

We first reviewed 5 clinical studies of antiasthma TCM herbal remedies published between 2005 and 2007. We then summarized possible mechanisms underlying their effects on the basis of data in the original articles, published abstracts, and available databases. Possible mechanisms include anti-inflammation, inhibition of airway smooth muscle contraction, and immunomodulation. Research on TCM herbal therapy for food allergy is rare, and we therefore focused on the effect and mechanism of action of food allergy herbal formula-2 on a murine model of peanut allergy and preliminary clinical study results.

Conclusion

Evidence from clinical studies supports beneficial effects of TCM herbal therapy on asthma. A number of mechanisms may be responsible for efficacy of these agents. Strong preclinical study data suggest the potential efficacy of food allergy herbal formula-2 for food allergy.

Key words: Complementary and alternative medicine, traditional Chinese herbal medicine, botanical drug, asthma, food allergy, T_H1/T_H1 balance

Abbreviations used: AHR, Airway hyperresponsiveness, ASHMI, Antiasthma herbal medicine intervention, CAM, Complementary and alternative medicine, DCT, Ding Chuan Tang, FAHF-2, Food allergy herbal formula-2, FDA, US Food and Drug Administration, IND, Investigational new drug, LWDHW, Lui-Wei-Di-Huang Wan, mMMDT, Modified Mai Men Dong Tang, NIH, National Institutes of Health, TCM, Traditional Chinese medicine