Herbal interventions for chronic asthma in adults and children

Chronic asthma is a inflammatory disease of the airways characterised by wheeze and breathlessness. Drug therapy is usually used to control symptoms but complementary medicine is often used, including herbal treatments, and the efficacy and safety of such treatments is not clear. We reviewed evidence from 27 trials covering 21 different herbal treatments in both adults and children from both in-patient and out-patient settings. In general, the reporting of trials was poor. The outcomes measured by the trials varied considerably which made it difficult to compare the results of studies that did look at the same treatment. On the basis of the available evidence it is not possible to show whether any of these herbal treatments can improve asthma symptoms. Further trials of high quality are needed to assess the use of herbal treatments in asthma.