Herbal Medicine in Children and Adults with Atopic Dermatitis: A Systematic Review and Meta-Analysis

Herbal medicine is widely used for dermatological diseases, particularly atopic dermatitis. This study aims to systematically review existing literature on the efficacy of both topical and systemic herbal interventions for atopic dermatitis across various age groups. Conducting a comprehensive search on MEDLINE/PubMed, Scopus, and the Cochrane Central Register of Controlled Trials (Central) until April 12, 2023, only randomized controlled trials (RCTs) were included. The review is reported following the PRISMA guidelines and was conducted in accordance to Cochrane recommendations. Two authors independently extracted details, including demographics, medication, control/placebo groups, outcomes, adverse events, and results, with quality assessment using the Cochrane risk of bias tool 2.0. A meta-analysis, utilizing the random-effects model, was conducted, and publication bias was assessed through funnel plot inspection. The quality of evidence adhered to GRADE working group recommendations. The primary focus was evaluating atopic dermatitis or pruritus severity. The review encompassed 51 RCTs (3763 participants). Of these, 31 RCTs explored 19 distinct herbs and five complex remedies, whereas 20 RCTs (1088 participants) specifically investigated evening primrose oil (EPO). Herbs such as sunflower, licorice, figs, coconut, EPO, indigo naturalis, licorice, mauve, St. John's wort, and a combination of aloe vera and olive oil were found to have evidence of efficacy in the local treatment of atopic dermatitis. A meta-analysis on systemic used EPO, involving 13 RCTs, found no significant difference in atopic dermatitis severity compared with placebo (SMD: 0.14; 95% CI [-0.45; 0.73], 13 RCTs). In conclusion, this review provides a nuanced perspective on herbal substance efficacy for atopic dermatitis. While the EPO meta-analysis failed to show a discernible benefit beyond placebo, individual herbal preparations showed promising results in RCTs included in this review. Nevertheless, larger, methodologically rigorous studies are essential to establish evidence for herbal remedies in atopic dermatitis treatment.