HENNA (LAWSONIA INERMIS L.): A COMPREHENSIVE REVIEW OF TRADITIONAL MEDICINE, BIOACTIVE CONSTITUENTS AND THERAPEUTIC POTENTIAL

Lawsonia inermis L. (Lythraceae), commonly known as henna or mehndi, is an important medicinal and cosmetic plant widely used in traditional systems of medicine, including Ayurveda, Unani, Siddha, and folk healthcare practices across Asia, Africa, and the Middle East. Besides its extensive use as a natural dye for skin, hair, and textiles, the plant possesses significant therapeutic potential owing to its rich phytochemical composition. Major bioactive constituents, including lawsone (2-hydroxy-1,4-naphthoquinone), flavonoids, phenolic acids, coumarins, xanthones, tannins, terpenoids, sterols, and essential oils, are responsible for its diverse biological activities. Traditionally, various plant parts have been used for the treatment of skin diseases, wounds, burns, inflammatory disorders, fever, jaundice, dysentery, microbial infections, and several gynecological ailments. Contemporary pharmacological studies have validated many of these traditional claims by demonstrating antioxidant, antimicrobial, antifungal, antiviral, anti-inflammatory, wound-healing, antidiabetic, hepatoprotective, nephroprotective, anticancer, and immunomodulatory properties through in vitro and in vivo investigations. Recent advances in phytochemical analysis, metabolomics, molecular docking, nanotechnology, and herbal drug standardization have further expanded the pharmaceutical and industrial potential of L. inermis. Green synthesis of metallic nanoparticles and the development of novel herbal formulations highlight its emerging applications in medicine, cosmetics, biotechnology, and food preservation. However, challenges related to phytochemical standardization, quality control, clinical validation, safety assessment, and sustainable utilization remain to be addressed. This review comprehensively summarizes the current knowledge on the botany, taxonomy, ethnomedicinal significance, phytochemistry, pharmacological activities, quality control, safety, conservation, and future therapeutic prospects of Lawsonia inermis. It also identifies existing research gaps and emphasizes the need for further multidisciplinary investigations to facilitate the development of safe, standardized, and evidence-based plant-derived therapeutics.