Nanoemulsion-Based Polyherbal Formulations for Acne Vulgaris: Formulation Approaches, Characterisation and Therapeutic Potential

Acne vulgaris is a long-standing inflammatory disorder of the pilosebaceous unit that predominantly affects adolescents and young adults and often persists into adulthood. The condition develops due to the combined influence of abnormal follicular keratinisation, excessive sebum secretion, microbial proliferation, and immune-mediated inflammation. Conventional therapies such as topical antibiotics, retinoids, and benzoyl peroxide are widely used; however, their long-term application is associated with adverse effects including skin irritation, erythema, photosensitivity, teratogenicity, and the emergence of antibiotic resistance. These limitations have intensified the search for safer and more effective therapeutic alternatives. Herbal medicines have gained increasing attention due to their antimicrobial, anti-inflammatory, antioxidant, and wound-healing properties, as well as their better patient tolerability. Despite their therapeutic potential, many herbal actives exhibit poor solubility, instability, and limited skin penetration, thereby limiting their clinical efficacy. Nanoemulsion technology has emerged as a promising topical drug delivery system that enhances the solubility, stability, and dermal penetration of phytoconstituents. Polyherbal nanoemulsion formulations, which combine multiple herbal actives, offer synergistic and multi-targeted therapeutic effects against acne pathogenesis. This review critically summarizes the current status of nanoemulsion-based polyherbal formulations for the management of acne vulgaris, with emphasis on key herbal actives such as garlic oil and Manuka honey, along with other supportive botanicals. Formulation strategies, characterization techniques, biological evaluation approaches, challenges, and future perspectives are comprehensively discussed. This review highlights recent advances in nanoemulsion-based polyherbal formulations and emphasizes their potential as safer and effective topical alternatives for acne management. Keywords: Acne vulgaris, Polyherbal formulation, Nanoemulsion, Garlic oil, Manuka honey, Topical drug delivery