"Taking drugs for a long term" is a qualitative expression of medication method based on the efficacy and safety of Chinese medicine, and the study on it is conducive to the full utilization of the efficacy and rational use of drugs. There are 148 drugs that can be taken for a long time recorded in Shen Nong's Classic of Materia Medica, accounting for 41% of the total drugs. This paper analyzed three-grade classification, natural qualities, four properties and five flavors, and efficacy features of the "long-term taking" drugs(LTTD), thus exploring the herbal source of traditional Chinese medicine health care and the rationality of effect accumulation by long-term taking. It was found that there were more than 110 top-grade LTTD in Shen Nong's Classic of Materia Medica, most of which were herbs, with sweet flavor, flat property, and no toxicity. The efficacies were mainly making body feel light and agile(Qingshen) and prolonging life. Eighty-three LTTD were included in the Chinese Pharmacopoeia(2020 edition). In the modern classification, tonic LTTD accounted for the most, followed by damp-draining diuretic LTTD and exterior-releasing LTTD. Twenty LTTD were included in the "List of Medicinal and Edible Products" and 21 were in the "List of Products Used for Health-care Food", involving in various modern health care effects, such as enhancing immunity, assisting in reducing blood lipids, and anti-oxidation. Shen Nong's Classic of Materia Medica is the classic source of traditional Chinese medicine health care, and its medication thought of taking drugs for a long term to accumulate effects has guiding significance for the regulation of sub-health and chronic diseases nowadays. The efficacy and safety of LTTD have been examined in practice for a long time, and some of the drugs are edible, which is unique in the whole cycle of health-care service, especially in line with the health-care needs in the aging society under the concept of Big Health. However, some records in the book are limited by the understanding of the times, which should be scientifically studied according to the Chinese Pharmacopoeia and the related regulations and technical requirements, under the attitude of eliminating falsifications and preserving the truth and keeping the right essence, so as to achieve further improvement, innovation, and development.