Topical herbal medicines for atopic eczema: a systematic review of randomized controlled trials

Abstract

Despite the availability of medicines with proven efficacy, many patients use complementary or alternative medicines (CAMs) to manage atopic eczema (AE). Due to the lack of objective information on topical CAMs, this systematic review evaluates the current evidence for the efficacy and safety of topical herbal preparations in AE. Using Cochrane systematic review methodology, PubMed, the Cochrane Library, the Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL (via EBSCO), MEDLINE (via EBSCO), Proquest Health and Medical Complete, GREAT and CAM-QUEST were searched from inception until June 2014. Bibliographies of retrieved studies were hand searched for further relevant trials. All controlled clinical trials of topical herbal medicines for AE in humans of any age were included regardless of the control intervention or randomization. Only English-language publications were considered. Eight studies met the inclusion criteria. Seven investigated extracts of single plants and one an extract from multiple plants. Only two studies that showed a positive effect were considered to have a low risk of bias across all domains (those of liquorice gel and Hypericum perforatum). In these two, the test product was reported to be superior to placebo. Despite variations in diagnostic criteria and lack of validated tools for outcome assessments in one of these, the promising results may warrant continued research in better-designed studies. No meta-analysis was performed due to heterogeneity in all studies. There is currently insufficient evidence of efficacy for any topical herbal extract in AE. Many studies had methodological flaws and even those showing efficacy were single trials with small patient cohorts.

Use of Complementary and Alternative Therapies in Outpatients with Atopic Dermatitis from a Dermatological University Department

“…The variability in treatment procedures together with the chronicity of the disease might stimulate an interest in complementary or alternative medications and treatments (CAM) [2]. Although CAM is not supported by scientific evidence [3, 4], it has been in great demand for decades [5] and shown to be more frequently used in chronic patients [6]. CAM use in dermatology is believed to be most frequent among AD patients but other diseases, including psoriasis and acne, are also associated with prevalent CAM use [7, 8].…”

Use of “natural” oils for moisturization: Review of olive, coconut, and sunflower seed oil

“…Patients may consider virgin coconut oil when using coconut oil and high‐linoleate SSO when using SSO. Thandar and colleagues recently demonstrated in a systematic review that extant data are insufficient for giving advice concerning the use of alternative topical therapies for AD, because few studies have been conducted, and many have methodological flaws . Despite the lack of evidence‐based research on the topic, providers who are aware of the literature can have a more informative and nuanced discussion with their patients about the appropriate use of alternative therapies.…”

What's new in atopic eczema? An analysis of systematic reviews published in 2016. Part 1: treatment and prevention

“…Thandar et al 18 assessed the evidence for topical herbal medicines. Of the eight RCTs included, only two small studies showed evidence of efficacy and were considered to have a low risk of bias: liquorice gel (90 participants) and Hypericum perforatum (St John's wort) cream (21 participants), both compared with placebo, prompting the conclusion that further high-quality studies are needed to assess these two treatments.…”