嗌痛，脉循胃系也。颔肿，脉循颈上颊也。肩痛，脉出肩解也。 难举，脉循 也。耳聋，脉入耳也。目
黄，脉入内、外 也。颊肿，颈、颔、肩、 、肘、臂外后廉痛，皆经脉所过之地。以上言经病，未言腑病；
言本经病，未言合病，然亦可类推也。
小肠主分泌水谷，为受盛之官。
本病（脏腑之病）
大便水谷利，小便短，小便闭，小便血，小便自利，大便后血，（大肠主大便，膀胱主小便，而小肠兼主
大小便，以分泌水谷也。小肠气痛，本腑病。）宿食夜热旦止。（以小肠为受盛之官。）
标病（经络之病）
身热恶寒，（手足太阳病同。）嗌痛颔肿，（同经。）口糜，（合胃经病，以脉循
胃系也。）耳聋。（同经。）
实热泻之
小肠承胃之下脘，而下输膀胱，大肠实热则不能泌别清浊，故用泻，下分二法。
气∶气分有热，则水谷不分，行水即以导热。
木通（通大小肠，导诸湿热。）猪苓（利湿利水。）滑石（利窍渗湿，泻热行水。）瞿麦（降心火，利小肠，
行水破血。）泽泻（利湿行水。）灯草（降心火，利小肠。）
血∶热入血分，则血妄行，清热所以凉血止血。
地黄（泻丙火，凉血生血。）蒲黄（生行血，熟止血。）赤茯苓（入心、小肠，利湿热。）栀子（泻心肺
邪热，下从小便出。）丹皮（泻血中伏火，凉血而生血。）
虚寒补之
小肠属火，化物出焉，虚寒则失其职，故用补，下分二法。
气∶胃为小肠上流，胃气虚则湿流小肠而水谷不分，调补胃气，即以补小肠之气也。
白术（燥湿和中，益阳补气。）楝实（导小肠热，引心包相火下行。）茴香（开胃调中，疗小肠冷气。）
砂仁（快气调中，通行结滞，入大小肠。）神曲（调中开胃，化水谷，消积滞。）扁豆（调脾暖胃，消暑除湿。
）
血∶血分寒虚，则多凝滞，补阳行气，所以活血而补血也。
桂心（辛走血，能补阳活血。）胡索（行血中气滞、气中血滞。）
本热寒之
不言本寒者，虚寒已见上条，省文也。
降火∶小肠与心为表里，心火太旺，往往下传于小肠，降心火所以清小肠之上流也。
黄柏（泻相火，补肾水。）黄芩（苦入心，寒胜热。）黄连（大苦大寒，入心泻火。）连翘（形似心。入
心经气分而泻火。）栀子（泻心、肺、三焦之火。）
标热散之
阳邪中上，阴邪中下。手太阳经脉在上，非寒邪所能干，故止言标热。
解肌∶阳邪每多自汗之证，故不用发表，且小肠经专主上部，与足阳明解肌不同。
本（辛温雄壮，为太阳风药。）羌活（搜风发表。）防风（解表去风，主上焦风邪。）蔓荆（轻浮升散，
主上部风邪。）
咽喉疼痛，是因为经脉循行经过胃的系带。下颌肿胀，是因为经脉循行经过颈部并上行至面颊。肩部疼痛，是因为经脉出于肩关节的缝隙。手臂难以抬起，是因为经脉循行经过[此处原文缺字，推测为腋或臂]。耳聋，是因为经脉进入耳中。眼睛发黄，是因为经脉进入内、外眦。面颊肿胀，以及颈部、下颌、肩部、[此处原文缺字]、肘部、手臂外侧后缘的疼痛，都是经脉所经过的部位。以上论述的是经脉本身的病变，尚未涉及腑的病变；论述的是本经的病变，尚未涉及合病（多经同病），但道理可以类推。
小肠主要功能是分泌和分别水谷，被称为“受盛之官”（接受和盛纳水谷的器官）。
本病（指脏腑内部的病变）
大便稀溏夹杂未消化食物，小便短少，小便闭塞不通，尿血，小便失禁或频数，大便后出血。（大肠主管大便，膀胱主管小便，而小肠兼管大小便，因为它负责分别清浊。小肠气痛，属于本腑的病变。）宿食停滞导致夜间发热，早晨热退。（因为小肠是受盛之官，负责容纳和腐熟水谷。）
标病（指经络表面的病变）
身体发热怕冷。（与手足太阳经的病证相同。）咽喉疼痛，下颌肿胀。（与同经有关。）口舌生疮糜烂。（与胃经相关，因为经脉循行经过胃的系带。）耳聋。（与同经有关。）
实证、热证用泻法治疗
小肠位于胃的下脘之下，向下输注于膀胱。如果大肠实热，就不能分别清浊，所以使用泻法，下面分为两种方法。
气分：气分有热，则水谷不能分别，通过利水来引导热邪排出。
木通（疏通大小肠，引导各种湿热。）猪苓（利湿利水。）滑石（通利窍道渗湿，泻热行水。）瞿麦（降心火，利小肠，行水破血。）泽泻（利湿行水。）灯草（降心火，利小肠。）
血分：热邪进入血分，则血液妄行，清热是为了凉血止血。
地黄（泻丙火，凉血生血。）蒲黄（生用行血，熟用止血。）赤茯苓（入心、小肠，利湿热。）栀子（泻心肺邪热，从小便排出。）丹皮（泻血中伏火，凉血而生血。）
虚证、寒证用补法治疗
小肠属火，负责化物，如果虚寒则失去其职能，所以使用补法，下面分为两种方法。
气分：胃是小肠的上游，胃气虚弱则湿气流入小肠导致水谷不分，调理补益胃气，也就是补益小肠之气。
白术（燥湿和中，益阳补气。）楝实（引导小肠热，引心包相火下行。）茴香（开胃调中，治疗小肠冷气。）砂仁（快气调中，通行结滞，入大小肠。）神曲（调中开胃，化水谷，消积滞。）扁豆（调脾暖胃，消暑除湿。）
血分：血分寒虚，则容易凝滞，补阳行气，从而活血补血。
桂心（辛味走血，能补阳活血。）延胡索（行血中气滞、气中血滞。）
本热用寒凉药治疗
不说本寒的原因，是因为虚寒已经在上面条目中提及，这是省略写法。
降火：小肠与心互为表里，心火太旺，往往下传于小肠，降心火就是为了清小肠的上游之火。
黄柏（泻相火，补肾水。）黄芩（苦味入心，寒性胜热。）黄连（大苦大寒，入心泻火。）连翘（形状像心，入心经气分而泻火。）栀子（泻心、肺、三焦之火。）
标热用发散法治疗
阳邪侵犯上部，阴邪侵犯下部。手太阳经脉在上部，不是寒邪所能干扰的，所以只谈论标热。
解肌：阳邪常常伴有自汗的症状，所以不使用发表药，而且小肠经专门主管上部，与足阳明经的解肌不同。
本（原文此处似有误或指代不明，结合语境可能指某种辛温药物或泛指风药，保留原意）（辛温雄壮，为太阳经的风药。）羌活（搜风发表。）防风（解表去风，主治上焦风邪。）蔓荆子（轻浮升散，主治上部风邪。）
Throat pain occurs because the meridian passes through the gastric system. Submandibular swelling occurs because the meridian passes through the neck and ascends to the cheek. Shoulder pain occurs because the meridian emerges from the shoulder joint gap. Difficulty in raising the arm is due to the meridian passing through [text missing, likely armpit or arm]. Deafness occurs because the meridian enters the ear. Yellowing of the eyes occurs because the meridian enters the inner and outer canthi. Cheek swelling, as well as pain along the posterior-lateral aspect of the neck, submandible, shoulder, [text missing], elbow, and arm, are all areas traversed by the meridians. The above discusses diseases of the meridians (Jing), not yet diseases of the Fu organs; it discusses diseases of the primary meridian, not yet combined diseases (He Bing) involving multiple meridians, but the principle can be extrapolated.
The Small Intestine is primarily responsible for separating and extracting nutrients from food and fluids, functioning as the "Official of Reception and Containment" (Shou Sheng Zhi Guan).
Primary Disease (Bing Ben - Diseases of the Zang-Fu organs):
Diarrhea with undigested food particles, short urine, urinary retention, hematuria, urinary incontinence or frequency, and bleeding after defecation. (The Large Intestine governs stool, the Bladder governs urine, while the Small Intestine governs both because it separates clear from turbid. Pain from Qi stagnation in the Small Intestine belongs to a disease of this Fu organ.) Retained food causing fever at night that subsides by morning. (Because the Small Intestine is the Official of Reception and Containment.)
Secondary Disease (Bing Biao - Diseases of the Meridians):
Fever and aversion to cold. (Same as Taiyang diseases of the Hand and Foot.) Throat pain and submandibular swelling. (Related to the same meridian.) Mouth ulcers/mucosal erosion. (Related to the Stomach meridian, as the vessel passes through the gastric system.) Deafness. (Related to the same meridian.)
For Excess-Heat patterns, use draining methods:
The Small Intestine is located below the lower epigastrium of the Stomach and drains downward into the Bladder. If there is excess heat in the Large Intestine, it cannot separate the clear from the turbid, so draining methods are used, divided into two approaches below.
Qi Level: Heat in the Qi level causes failure to separate food and fluids; promoting urination guides heat out.
Tong Cao (Akebia Caulis): Unblocks the Large and Small Intestines, guides damp-heat. Zhu Ling (Polyporus): Promotes diuresis and removes dampness. Hua Shi (Talcum): Opens orifices, leaches out dampness, drains heat, and promotes water metabolism. Qu Mai (Dianthus Herb): Descends Heart Fire, benefits the Small Intestine, promotes water metabolism, and breaks blood stasis. Ze Xie (Alisma Rhizome): Promotes diuresis and moves water. Deng Xin Cao (Juncus Medullary Pith): Descends Heart Fire, benefits the Small Intestine.
Blood Level: Heat entering the Blood level causes reckless bleeding; clearing heat cools the blood and stops bleeding.
Di Huang (Rehmannia Root): Drains Bing Fire, cools blood, and generates blood. Pu Huang (Typha Pollen): Raw form moves blood, cooked form stops bleeding. Chi Fu Ling (Red Poria): Enters the Heart and Small Intestine, promotes diuresis and removes damp-heat. Zhi Zi (Gardeniae Fructus): Drains pathogenic heat from the Heart and Lungs, excreted via urine. Mu Dan Pi (Moutan Cortex): Drains latent fire in the blood, cools blood, and generates blood.
For Deficiency-Cold patterns, use tonifying methods:
The Small Intestine belongs to Fire and is responsible for transformation. Deficiency-cold leads to loss of function, so tonifying methods are used, divided into two approaches below.
Qi Level: The Stomach is the upstream source of the Small Intestine. If Stomach Qi is deficient, dampness flows into the Small Intestine causing failure to separate food and fluids. Regulating and tonifying Stomach Qi also tonifies Small Intestine Qi.
Bai Zhu (Atractylodis Macrocephalae Rhizoma): Dries dampness, harmonizes the middle, benefits Yang, and tonifies Qi. Li Shi (Toosendan Fruit): Guides heat from the Small Intestine, draws Minister Fire from the Pericardium downward. Hui Xiang (Foeniculum Vulgare Fruit): Opens the stomach, regulates the middle, treats Cold Qi in the Small Intestine. Sha Ren (Amomi Fructus Rotundus): Moves Qi, regulates the middle, unblocks stagnation, enters the Large and Small Intestines. Shen Qu (Massa Medicata Fermentata): Regulates the middle, opens the stomach, transforms food and fluids, eliminates stagnation. Bian Dou (Lablab Seed): Regulates the Spleen, warms the Stomach, dissipates summerheat, and removes dampness.
Blood Level: Cold-deficiency in the Blood level leads to stagnation; tonifying Yang and moving Qi activates blood and nourishes blood.
Gui Xin (Cinnamomi Cortex): Pungent flavor travels to the blood, can tonify Yang and activate blood. Hu Suo (Curcuma Zedoaria Rhizome / Curcuma Phaeocaulis Rhizome): Moves Qi stagnation in blood and Blood stagnation in Qi.
For Primary Heat, use cooling methods:
Primary Cold is not mentioned here because Deficiency-Cold was covered in the previous section; this is an omission for brevity.
Descend Fire: The Small Intestine and Heart are exterior-interior pairs. Excessive Heart Fire often transmits downward to the Small Intestine; descending Heart Fire clears the upstream heat of the Small Intestine.
Huang Bo (Phellodendri Cortex): Drains Minister Fire, tonifies Kidney Water. Huang Qin (Scutellariae Radix): Bitter flavor enters the Heart, cold nature overcomes heat. Huang Lian (Coptidis Rhizoma): Greatly bitter and cold, enters the Heart to drain fire. Lian Qiao (Forsythiae Fructus): Shape resembles the heart; enters the Qi level of the Heart meridian to drain fire. Zhi Zi (Gardeniae Fructus): Drains fire from the Heart, Lungs, and San Jiao.
For Secondary Heat, use dispersing methods:
Yang pathogens attack the upper body, Yin pathogens attack the lower body. The Hand Taiyang meridian is in the upper part and is not easily affected by Cold pathogens, so only Secondary Heat is discussed.
Release the Muscle Layer: Yang pathogens often present with spontaneous sweating, so releasing-the-exterior methods are not used. Moreover, the Small Intestine meridian specifically governs the upper part, differing from the muscle-layer-releasing method of the Foot Yangming meridian.
Ben [Text unclear/likely error in original, possibly referring to a specific herb or generic wind medicine]: (Pungent-warm and potent, a wind medicine for the Taiyang meridian.) Qiang Huo (Notopterygii Rhizoma et Radix): Expels wind and releases the exterior. Fang Feng (Saposhnikoviae Radix): Releases the exterior and dispels wind, primarily treating Wind pathogens in the Upper Jiao. Man Jing Zi (Vitalbae Fructus): Light, floating, ascending, and dispersing, primarily treating Wind pathogens in the upper part.