Kriyakala: A Classical Framework for Understanding Disease Progression

Ayurveda regards disease as the end point of a graded process of Dosha vitiation and not as a sudden event. Kriyakala (Shatkriyakala), described most systematically by Acharya Sushruta, divides this process into six recognisable stages: Sanchaya, Prakopa, Prasara, Sthanasamshraya, Vyakti and Bheda. Each stage offers a distinct therapeutic opportunity. Aim: To compile the classical descriptions of Kriyakala and to discuss their clinical relevance to early diagnosis, prevention and treatment planning. Materials and Methods: A conceptual, literary review was carried out. Primary sources were the Sushruta Samhita, Ashtanga Hridaya and Charaka Samhita with their classical commentaries. Secondary sources were peer-reviewed and indexed articles located through PubMed, DHARA and Google Scholar. Descriptions were compared across texts and arranged stage by stage. Results: The classics describe six stages, each with characteristic symptoms and a matching line of management. Sanchaya, Prakopa and Prasara are largely preventable and reversible. Sthanasamshraya marks the onset of the prodrome (purvarupa). Vyakti and Bheda are stages of established and complicated disease. The framework is linked to ritucharya, as Doshas accumulate in one season and aggravate in the next. Conclusion: Kriyakala is a preventive, stage-based model of Samprapti that is broadly comparable to the natural history of disease in modern medicine. Its greatest value is in lifestyle disorders, where functional change precedes diagnosable disease. Objective, validated criteria for the early stages are needed.