Chen Xiuyuan studied Confucianism and medicine since childhood. Zeng studied medicine under Quanzhou famous doctor Cai. In the fifty-seventh year of Qianlong (1792), he was appointed as a magistrate in Zhiliwei County, and used effective prescriptions to treat people suffering from epidemic diseases after floods. In the 24th year of Jiaqing (18 19), he returned from his illness and gave lectures in Jingshan Caotang, Songshan and Changle to train medical students. There were many disciples studying medicine at that time.
In the era of Chen Xiuyuan, in order to cope with outpatient service, most doctors only studied the medical books and prescriptions of various doctors since the Tang and Song Dynasties, trying to find out several prescriptions for treating diseases, but were not interested in classic medical works, theoretical works, Neijing, Difficult Classic, Shennong Herbal Classic, Treatise on Febrile Diseases and synopsis of the Golden Chamber. Even less willing to work hard to study these works.
Chen Xiuyuan thinks it is abnormal to despise the basic theory of TCM. In order to reverse this academic spirit, in the twenty-fourth year of Jiaqing (18 19), Chen Xiuyuan retired in his later years and gave lectures in Inoue Caotang, Songshan, Fujian, which not only inherited his own experience in studying these Chinese medicine classics for decades, but also strongly appealed to other medical scientists to pay attention to this research. Many people from all over the country attended his lecture.
In medical theory, Chen Xiuyuan especially admired Zhang Zhongjing, who was one of the backbone figures in maintaining typhoid fever school and the most influential school of respecting classics and worshipping the ancient times after Zhang Zhicong and Zhang Xiju. In the debate on typhoid fever research, he strongly opposed Fang Youzhi and Yu's "wrong simplified version", and thought that Zhang Zhongjing's theory had been completely handed down from generation to generation in the second edition of Treatise on Febrile Diseases, and could not be changed or accepted casually. His representative works in the study of Treatise on Febrile Diseases and Synopsis of the Golden Chamber include Treatise on Febrile Diseases, Synopsis of the Golden Chamber and Series of Explanations of Treatise on Febrile Diseases. The first two books have been revised three times, and the history books call them "many inventions, which are rare books in the world". He also arranged the prescriptions and treatments in Treatise on Febrile Diseases and synopsis of Golden Chamber into Changsha Square Enclosed, Typhoid True Square Enclosed and Golden Chamber Square Enclosed, which was convenient for memorizing and reciting, and was very helpful for learning and understanding Treatise on Febrile Diseases and synopsis of Golden Chamber in the future. Although some people say that Chen Xiuyuan's annotations on ancient books are unique, the wide spread of his above works is mainly due to the characteristics of his research, which provides an introductory ladder for later scholars, especially beginners, to study Zhang Zhongjing's ancient books.
In clinical treatment, Chen Xiuyuan is good at warming spleen and kidney to treat miscellaneous diseases, but he doesn't like cold and nourishing yin. As he himself said, "Everyone knows that cold medicine can't be taken for a long time. Only nourishing yin and reducing fire, lukewarm products are the most misleading. If you don't like cold, Gu Lie can't abandon the cold side. " Although he admits that cold prescriptions such as Zishen Pill, Sisheng Pill and Qingzao Jiufei Decoction can replenish qi and are indispensable prescriptions for treating tuberculosis (a consumptive disease such as tuberculosis), they can only be used temporarily. The isothermal prescriptions of Baoyuan Formula, Liujunzi Decoction, Wuwei Gong Yi Powder, Guipi Decoction and Fuzi Lizhong Decoction are highly praised for their effects of "tonifying deficiency and reducing fever, eliminating diseases", "benefiting essence and qi, and nourishing vitality", which are called "the wonderful way to replenish fire and make water".