Methodological Aspects in the Preparation of Naga Anjana Shalaka”: a Ayurvedic Review

Ayurvedic ophthalmology (Netra Roga Cikitsa) emphasizes the use of specialized instruments known as Shalakas. Among them, the Naga Anjana Shalaka is uniquely described for its application in ocular disorders. The efficacy and safety of this instrument depend on its precise preparation, which involves classical Shodana (purification) and Shalaka Nirmana (rod formation) techniques. Objective: To systematically review and highlight the methodological aspects of Naga Anjana Shalaka preparation as documented in classical Ayurvedic texts, and to discuss its relevance in the context of contemporary pharmaceutical and ophthalmic standards. Methods: Primary references from Susrutha Samhitha, Cakradatta, Yoga Ratnakara, Sharangadhara Samhitha, Yogatarangini, and Sara Saṃgraha were critically examined. The processes of Naga shodhana using Triphala kwatha, Bhringaraja swarasa, Shunti kwatha, Go-dugdha, Go-mutra, Ghrita, and Madhu were analyzed, along with descriptions of rod dimensions, design, and application. Results: The review reveals that the preparation involves sequential Sodhana by heating and quenching Naga in herbal and animal-derived media, followed by shaping into a rod (shalaka) of approximately 8–12 angula (8-9 cm). The tip is fashioned as kalaya-akara (pea-shaped) or tri-bhujagra (triangular), ensuring smoothness and safety for ophthalmic use. These methodological steps not only detoxify Naga but also impart therapeutic attributes to the instrument. Conclusion: The preparation of Naga Anjana Shalaka reflects a meticulous blend of Rasasastra and ophthalmic surgical principles. Standardization of its preparation and scientific validation of its safety are crucial for integrating this classical ophthalmic tool into contemporary clinical practice.