Indications for Emetic Therapy: When pathogenic factors are knotted in the Middle Jiao (Middle Burner), food stagnates in the Tai Cang (Stomach), and phlegm-fluids lie latent within. Pain in the chest region, a large pulse at the Right Guan position, or conversely a deep pulse, or pulses present in the lower part but absent in the upper part, all indicate suitability for emetic therapy. Thus it is said that when the disease is located above the diaphragm or in the chest, emesis is indicated. When food accumulation is in the Upper Jiao (Upper Burner), accompanied by chest fullness and excessive phlegm, emesis is indicated. Hua Tuo stated: "In Shanghan (Cold Damage) after three to four days, when pathogens are in the chest, emesis is indicated." Generally, for emetic therapy, Gengti San (Melon Seed Powder) may be used, or light salt water, or warm tea soup; for those with weak constitutions, Ren Shen Lu (Deer Antler Velvet of Ginseng) is used. However, this is not as effective as the family-secret emetic method: to disperse wind, use only Fang Feng (Saposhnikovia Root); to resolve nodulation, use only Zhi Ke (Bitter Orange); to relieve vexation, use only Shan Zhi (Gardenia Fruit); for body pain, use only Qiang Huo (Notopterygium Rhizome); for headache, use only Chuan Xiong (Ligusticum Rhizome). Decoct these in water, take warm, and after a short while, induce vomiting by tickling the throat with a bird feather. This method does not damage Stomach Qi.

Contraindications for Emetic Therapy: When the disease is not in the upper part, and there is no stagnation in the chest, emesis is unnecessary. Zhang Zhongjing stated: "A fine pulse at the Guan position is due to the physician's error in using emesis." If Taiyang disease is treated with emesis, and the patient instead loses aversion to cold and has no desire for food, this indicates internal heat and vexation caused by the physician's erroneous emesis. In Shaoyang wind-strike, where hearing is lost in both ears, eyes are red, and there is chest fullness and vexation, neither emesis nor purgation should be used. Therefore, emetic therapy is contraindicated for the elderly, the weak, and those with deficiency. It is contraindicated for those with chronic illness and weakness. It is contraindicated for those with internal injury to the Yuan Qi (Original Qi). It is contraindicated for those with empty and large pulses. It is contraindicated for those with fine pulses lacking spirit. It is contraindicated for those with weak Stomach Qi and poor appetite. It is contraindicated for those suffering from frequent dizziness and vertigo. It is contraindicated during pregnancy and postpartum. It is contraindicated after the ulceration of carbuncles and sores, or following traumatic injuries with blood loss. Although ancients used sweating, emesis, and purgation to treat external contraction, emesis and purgation require extreme caution.

Zhang Zhongjing detailed the methods of warming the meridians and rescuing the interior in the chapters on the Three Yin Meridians. He stated: "Taiyin disease with spontaneous diarrhea and no thirst is due to cold in the zang organs; it should be warmed." "For Shaoyin disease with vomiting and diarrhea, cold extremities, and severe restlessness desiring death, Wu Zhu Yu Tang (Evodia Decoction) is the primary treatment." "For Shaoyin disease with diarrhea and a faint pulse..." "For Shaoyin disease with diarrhea passing undigested food, presenting with interior cold and exterior heat, Tong Mai Si Ni Tang (Pulse-Rescuing Cinnamon Twig Decoction) is indicated." "For Shaoyin disease with a deep pulse, urgent warming is required, and Si Ni Tang (Frigid Extremities Decoction) is suitable." "For Shaoyin disease where food is vomited immediately upon entering the mouth, if there is cold above the diaphragm causing dry heaving after drinking water, emesis must not be used; urgent warming is required." "For Shaoyin disease with diarrhea, faint and thin pulses, vomiting, sweating, frequent defecation but scant output, warming is indicated." "For Jueyin disease with cold extremities and a fine pulse nearly imperceptible, Dang Gui Si Ni Tang (Angelica Frigid Extremities Decoction) is the primary treatment." He also stated: "In Shanghan with a rapid pulse and cold extremities, moxibustion may be applied." All the above are Yin syndromes of cold affecting the Three Yin Meridians, thus warranting warming of the meridians and rescue of the interior.