Hair Growth-Promoting Potential of Semecarpus anacardium: Mechanistic Insights and Pharmacological Evidence

Traditional herbal medicine remains a cornerstone of healthcare, offering remedies for conditions where modern therapies are limited. Semecarpus anacardium Linn. (marking nut; “Bhallataka”) is a well-known Ayurvedic plant with diverse pharmacological properties and emerging potential in hair growth promotion. Preclinical and ethnomedicinal evidence suggest that its bioactive constituents particularly anacardic acid, biflavonoids, and phenolic compounds exert antioxidant, anti-inflammatory, and antimicrobial actions that help create a favorable scalp environment. These effects protect hair follicles from oxidative stress, regulate inflammatory pathways, and enhance follicular cycling, thereby supporting the transition from telogen to anagen phase and stimulating stem cell activity. Additionally, modulation of signaling pathways such as NF-κB, Wnt/β-catenin, and Shh underpins its mechanistic role in follicle regeneration and proliferation. Despite these promising effects, raw preparations of S. anacardium are associated with significant toxicity, including dermatitis and systemic reactions, underscoring the importance of detoxification processes (Shodhana) and safe formulation strategies. Current data are largely limited to in vitro and animal models, with a paucity of standardized human clinical trials. This review integrates traditional knowledge with modern pharmacological insights, highlighting S. anacardium as a candidate for developing safe, plant-based interventions against hair loss. Future work should focus on standardized extraction methods, novel delivery systems, and well-designed clinical evaluations to validate its efficacy and safety in humans.