Nanhai Jigui Neifa Zhuan: exploration of and research on hygiene, medicine and health care knowledge in ancient India.

Background: The famous Tang Dynasty monk Yi Jing travelled to ancient India in 671 AD, visited more than 30 regions and returned to China in 695 AD. He wrote Nanhai Jigui Neifa Zhuan, which he completed in 691 AD. It describes the basic rules, namely 'Inner Dharma' (Neifa,内法) that Buddhist sites and monks should follow in their daily lives. Additionally, the author provided an overview of ancient Indian Buddhist medicine, covering aetiology, diagnosis, medication, acupuncture, health preservation and other aspects, which exhibited distinct characteristics. Methods: This article first delves into the original text of Nanhai Jigui Neifa Zhuan by reading it thoroughly and extracts core chapters related to hygiene, medicine and health care. Later, the extracted information is meticulously classified and organised. Lastly, through a systematic literature review, keywords search, data screening and comparative analysis, an in-depth and comprehensive exploration and analysis of Nanhai Jigui Neifa Zhuan is conducted within the domains of hygiene, medicine and health care. Results: Nanhai Jigui Neifa Zhuan emphasizes the importance of personal hygiene for ancient Indian monks and introduces the basic theories of ancient Indian medicine. It compares ancient Indian and Chinese medicinal materials, highlighting their respective roles in treating different diseases. Furthermore, it briefly discusses the storage and processing of ancient Indian medicinal materials, poisoning and toxicology, and ancient Indian health preservation ideologies. Conclusion: A comprehensive and in-depth study of traditional ancient Indian medicine, including Buddhist medicine and Ayurveda, and its application in the religious environment and communities of the Tang Dynasty (618–907 AD) aids in understanding the treatment methods and health practices of ancient Indian medicine. Additionally, it facilitates a deeper understanding of the similarities, differences and exchange between Chinese and Indian medicine, thereby opening up new horizons for future research. [ABSTRACT FROM AUTHOR]