Chinese herbal medicine for atopic eczema : intervention review

Atopic eczema (eczema in short) is a common skin condition, where skin changes occur and cause redness, scaling, swelling, and skin thickening due to chronic scratching. It is associated with loss of sleep, self-esteem, and quality of life. The frequency of eczema has increased over the past 10 years. A former Cochrane review published in 2004 found some evidence of a possible benefit of using oral Chinese herbal medicine (CHM) for eczema; however, the results from only 4 included studies were inconclusive and need to be updated (those four studies have not been included in this update as they investigated a product that has been withdrawn from the market since 2004). As well as updating that review, we have also widened the scope of the review to assess the effects of topical CHM for eczema. We wrote a new protocol to expand the scope of this review. This review included 28 randomised controlled trials (RCTs), with 2306 children and adults, of which 4 compared CHM to placebo, 22 to conventional medications, and 2 to CHM taken by mouth. Most of the included studies reported a higher number of participants who had recovered and significantly improved, with less itching in the CHM groups than the control groups. Where CHM was compared to conventional drugs, although the total effectiveness rate outcome was superior with CHM, it was based on very low quality evidence. One study reported that the quality of life (QoL) score in the CHM group was better than in the placebo group after using a CHM formula taken by mouth for 12 weeks. We assessed most of the studies as at high 'risk of bias' and therefore not of good quality, and there was substantial inconsistency between the studies, so any positive effect in CHM must be treated with caution. One study reported one severe adverse event. Minor adverse events were observed in 24 studies, including temporary elevation of enzymes in 3 cases, which was reversed soon after stopping CHM. Eight included studies received government funding. We could not find conclusive evidence that CHM taken by mouth or applied to the skin was of benefit to children or adults with eczema. Well-designed, adequately powered RCTs are needed to evaluate the efficacy and safety of CHM for eczema.