神农本草经·上卷
上藥一百二十種為君，主養命以應天，無毒，多服久服不傷人，欲輕身益氣不老延年者，本《上經》。
中藥一百二十種為臣，主養性以應人，無毒，有毒，斟酌其宜，欲遏病補虛羸者，本《中經》。
下藥一百二十五種為佐使，主治病以應地，多毒，不可久服，欲除寒熱邪氣、破積聚、愈疾者，本《下經》。
藥有君臣佐使，以相宣攝合和者，宜用一君二臣五佐，又可一君三臣九佐使也。
藥有陰陽配合，子母兄弟，根莖花實草石骨肉。有單行者，有相須者，有相使者，有相畏者，有相惡者，有相反者，有相殺者。凡此七情和合視之，當用相須相使良者，勿用相惡相反者。若有毒宜制，可用相畏相殺者，不爾，勿合用也。藥有酸鹹甘苦辛五味，又有寒熱溫涼四氣及有毒無毒，陰乾暴乾，採治時日，生熟，上地所出，真偽陳新，並各有法。
藥性有宜丸者，宜散者，宜水煮者，宜酒浸者，宜膏煎者，亦有一物兼宜者，亦有不可入湯酒者，並隨藥性，不得違越。
凡欲治病，先察其源，先候病機。五臟未虛，六腑未竭，血脈未亂，精神未散，服藥必活。若病已成，可得半愈。病勢已過，命將難全。
若用毒藥療病，先起如黍粟，病去及止。不去，倍之；不去，十之。取去為度。治寒以熱藥，治熱以寒藥。飲食不消，以吐下藥。鬼注蠱毒，以毒藥。癰腫瘡瘤，以瘡藥。風濕，以風濕藥。各隨其所宜。
病在胸鬲以上者，先食後服藥。病在心腹以下者，先服藥而後食。病在四肢血脈者，宜空腹而在旦。病在骨髓者，宜飽滿而在夜。
夫大病之主，有中風、傷寒、溫瘧、中惡、霍亂、大腹、水腫、腸澼下利、大小便不通、賁肫、上氣、咳逆、嘔吐、黃疸、消渴、留飲、澼食、堅積癥瘕、驚邪、癲癇、鬼注、喉痺、齒痛、耳聾、目盲、金創、踒折、癰腫、惡瘡、痔、瘺、癭瘺、男子五勞七傷、虛乏羸瘦，女子帶下、崩中、血閉，蟲蛇蠱毒所傷，此皆大略，宗兆。其間變動枝節，各宜依端緒以取之。
The 120 superior drugs serve as "rulers" (jun), governing the nourishing of life in correspondence with Heaven. They are non-toxic; taken in large amounts or over a long time, they do not harm a person. Those wishing to lighten the body, boost qi, resist aging, and prolong life should base themselves on the Upper Classic (上經).
The 120 middle drugs serve as "ministers" (chen), governing the nourishing of one's nature in correspondence with Man. Some are non-toxic, some are toxic — their suitability must be weighed with care. Those wishing to check disease and supplement deficiency and weakness should base themselves on the Middle Classic (中經).
The 125 inferior drugs serve as "assistants and envoys" (zuoshi), governing the treatment of disease in correspondence with Earth. Most are toxic and should not be taken over a long time. Those wishing to eliminate cold and heat pathogenic qi, break up accumulations and masses, and cure illness should base themselves on the Lower Classic (下經).
Drugs have the roles of ruler, minister, assistant, and envoy, combined so as to mutually direct and regulate one another. One should use one ruler, two ministers, and five assistants; alternatively, one ruler, three ministers, and nine assistants and envoys.
Drugs have yin-yang pairings, like mother and child, elder and younger brother — root, stem, flower, fruit, herb, mineral, bone, and flesh. There are those that act alone, those that mutually reinforce each other, those that mutually guide each other, those that mutually restrain each other, those that mutually dislike each other, those that mutually conflict with each other, and those that mutually suppress each other. These seven relationships must all be weighed when combining drugs: one should use those that mutually reinforce or mutually guide well, and avoid those that mutually dislike or conflict. If a drug is toxic, its toxicity should be moderated — one may use those that mutually restrain or mutually suppress it; otherwise they should not be combined. Drugs have the five flavors — sour, salty, sweet, bitter, and pungent — and the four natures — cold, hot, warm, and cool — as well as being toxic or non-toxic. Drying in the shade or in the sun, the timing of gathering and processing, whether used raw or prepared, the region of origin, and whether genuine or adulterated, old or fresh — each of these has its proper method.
By nature, some drugs are suited to being made into pills, some into powders, some to be boiled in water, some steeped in wine, some rendered into pastes by decoction; some substances suit several of these methods at once, and some must not be put into decoctions or wine. All must follow the nature of the drug — this must not be violated.
Whenever one wishes to treat disease, first examine its origin and observe the mechanism of the illness. If the five viscera are not yet depleted, the six bowels not yet exhausted, the blood vessels not yet in disorder, and the spirit not yet dispersed, then taking medicine will surely save the patient. If the disease has already become established, only half a cure may be achieved. If the course of the disease has already passed its critical point, life will be hard to preserve.
If toxic drugs are used to treat disease, begin with a dose as small as a millet grain, and stop once the disease is gone. If it is not gone, double the dose; if still not gone, increase it tenfold. Take the disappearance of the disease as the measure. Treat cold with hot drugs, and heat with cold drugs. For indigestion of food and drink, use drugs that induce vomiting or purging. For ghost-attachment and gu-poisoning, use toxic drugs. For carbuncles, swellings, sores, and tumors, use sore-treating drugs. For wind-damp, use wind-damp drugs. Each should follow what is appropriate to it.
When disease is above the chest and diaphragm, eat first and take the medicine afterward. When disease is below the heart and abdomen, take the medicine first and eat afterward. When disease is in the limbs and blood vessels, medicine should be taken on an empty stomach, in the morning. When disease is in the bone marrow, medicine should be taken after a full meal, at night.
The principal categories of major disease include: wind-stroke, cold-damage disorders, warm malaria, attack by pestilence, sudden turmoil, abdominal distension, edema, dysenteric disorders with diarrhea, obstruction of urination and defecation, running-piglet qi, ascending qi, cough with counterflow, vomiting, jaundice, wasting-thirst, retained fluids, food stagnation, hardened accumulations and masses, fright-evil, epilepsy, ghost-attachment, throat obstruction, toothache, deafness, blindness, wounds from metal weapons, sprains and fractures, carbuncles and swellings, malignant sores, hemorrhoids, fistulas, goiter and fistulous swellings; in men, the five taxations and seven damages, deficiency and emaciation; in women, vaginal discharge, flooding, and amenorrhea; and injuries from insects, snakes, and gu-poison. These are but the general outline, the root patterns — the branching variations within each should be traced and addressed according to their particular thread.