Efficacy and Safety of Seawater Therapy Versus Non-pharmacological Interventions for Atopic Dermatitis: A Systematic Review.

Abstract

Marine water-based topical creams have been proposed as non-pharmacologic treatments for atopic dermatitis (AD), leveraging their mineralized nature to control inflammation, restore the skin barrier, and inhibit microbial colonization. However, their clinical efficacy and safety remain insufficiently characterized in existing observational and controlled studies. This systematic review aims to evaluate the effectiveness and safety of seawater and marine mineral-based therapies for patients with AD. A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidance. Randomized controlled trials and observational studies that investigated seawater or marine mineral-based treatments for AD were included. Seven databases were searched from April 2025 to September 10, 2025, using comprehensive Boolean and MeSH-based strategies. Extracted data included study design, intervention details, validated severity scores such as the Scoring Atopic Dermatitis (SCORAD) index, microbial colonization data, and adverse event profiles. Risk of bias was assessed with Risk of Bias (RoB) 2.0 and Risk Of Bias In Non-randomized Studies - of Interventions (ROBINS-I) tools. No review protocol was registered. Quantitative analysis of the 10 included studies demonstrated mean SCORAD improvements ranging from 26% to 55% in intervention groups. One trial reported a reduction from 45±4 to 7±1 in SCORAD, and another observed a 46±7.71% reduction with corticosteroids compared with 26±9.4% with thermal balneotherapy (therapeutic bathing in mineral water; p<0.03). Dead Sea climatotherapy (treatment in the unique climatic and mineral environment of the Dead Sea) and synchronous balneophototherapy (combined mineral water bathing with ultraviolet light therapy) consistently outperformed comparators in reducing severity scores. Qualitative findings revealed improvements in stratum corneum hydration, transepidermal water loss (TEWL, a measure of skin barrier integrity), and microbial composition, with marked reductions in <i>Staphylococcus aureus</i> colonization and enhanced microbial diversity. Adverse events were minimal and mild. In conclusion, seawater therapy demonstrated moderate clinical effectiveness in reducing AD severity and enhancing skin barrier function, with a favorable safety profile. These findings underscore the need to standardize treatment protocols and conduct larger trials to confirm long-term efficacy and reproducibility.