Not over a breast lump, redness or warmth; have a doctor check it.
乳根 Rugen
“Milk Root” · ST18
Foot Yangming · 18 of 45
Where. Directly below the nipple, at the root of the breast, in the fifth gap between the ribs.
For. Low milk supply, cough, chest pain.
Press. Gentle pressure, about a minute each side.
Caution. Not over a breast lump, redness or warmth; have a doctor check it.
乳根，在乳下一寸六分陷者中按 · Press with me
Six slow breaths
About a minute. Press as you breathe out, ease as you breathe in.
鄰 · Neighbouring leaves
Where Rugen Sits on the Lower Chest
The dataset places Rugen on the chest, directly below the nipple, at the root of the breast, in the fifth intercostal space, four cun lateral to the anterior midline. Unpacked piece by piece: a cun is the traditional proportional unit taken from the person being examined rather than from a ruler, so the same written distance lands differently on broad and slight frames. The recorded four cun is the very distance that separates the nipple from the breastbone line, because classical charts treat the centre of the nipple itself as sitting on the four-cun line. That is why the two halves of the location agree with each other: “directly below the nipple” and “four cun lateral to the midline” describe one vertical line, not two competing coordinates.
Counting the spaces makes the address concrete. The first groove your fingertip meets below the collarbone is the first intercostal space; five grooves down brings you to the fifth. The search is shorter than that sounds, because the neighbouring record for Ruzhong (ST17) places the centre of the nipple in the fourth intercostal space and notes that the point serves chiefly as a landmark — so from the nipple you simply cross one intercostal space straight down. Under the fingertips lies the soft fullness where breast tissue settles onto the chest wall, padded over the pectoralis muscle, with ribs and their gentle gaps beneath.
The neighbourhood confirms the address. From Qihu (ST13) at the lower border of the clavicle’s midpoint, the recorded stations step down the four-cun line one intercostal space at a time: Kufang (ST14) in the first space, Wuyi (ST15) in the second, Yingchuang (ST16) in the third, Ruzhong at the nipple centre in the fourth, and Rugen closing the sequence in the fifth. Reading the ladder together shows why a finger that drifts a groove too high has found a different point, and why losing count simply means returning to the nipple and measuring down a single time, slowly. Both sides carry the mirror-image pair, and the record treats them alike.
A Self-Palpation Walkthrough
Sit upright on a firm chair with both feet down and shoulders released, so the chest muscles soften. Find the centre of the nipple on one side and rest the pads of your index and middle fingers there. Slide straight down the chest wall — not outward, not inward — until your fingertips settle into the next shallow groove between ribs, right where the breast tissue meets the chest wall: that groove is the fifth intercostal space, and level with it lies Rugen. Repeat the whole search on the other side so both receive the same careful attention.
A few quiet confirmations help before any pressing begins. Touch feather-light and compare sides: many people notice a faint, dull awareness at the true spot and little sensation a thumb-width away. Let a slow breath move under your fingertips — the groove widens slightly as the ribs lift. Check the horizontal clearance too: the spot should sit well away from the breastbone, out on the nipple line, consistent with the recorded four cun from the midline. If everything feels silent, reseat the fingers half a thumb-width in some direction and search again patiently; the point is a small zone, not a pinhead.
The usual slips come from hurry. Dropping more than one groove below the nipple carries you past the recorded location, down toward where chest becomes upper abdomen — and once the channel reaches the abdomen its stations move inward toward the midline, so drifting low and inward together loses the line entirely. Drifting sideways off the nipple line finds unremarkable ground either way. And the instinct to press hard to “make sure” teaches nothing: the landmarks announce themselves to patient, light touch. When in doubt, return to the centre of the nipple and measure down once, slowly.
Reading the Name: Milk Root
Two characters, one clear picture. Ru 乳 carries the everyday senses of milk and, by extension, the breast — an ancient character whose oldest recorded forms are read as an image of nursing. Gen 根 means root: the part of a plant that anchors it in soil and draws up nourishment, extended in ordinary language to the base or foundation of anything. Together, Rugen renders naturally as Milk Root or Breast Root. The name is first and foremost a description of place: this point occupies the base where the breast settles onto the chest wall, the way a trunk meets the ground that holds it.
Commentators in the point-name tradition have read the characters this way for centuries, taking geography rather than physiology as their subject. Like the gates, valleys, courtyards, and storehouses scattered along the channels, “root” belongs to the family of body-landscape metaphors that teach location first and theory second. Still, the image does honest work: roots anchor and feed, and a name that pictures the breast rooted to the chest wall tells you both where the point lives and how firmly the tradition understood the two to belong together. Memorise the metaphor and you have memorised the address.
In pinyin the name is written Rugen, with tone marks the dictionaries spell out precisely. Ru takes the third tone — the dipping tone, which starts mid-range, falls low, then rises again. Gen holds the first tone — high, flat, and sustained, the level call of a tuning fork. Spoken plainly the name falls into two beats, dip then level: ru-gen. The hanzi pair is compact enough to recognise at a glance, and knowing that it means milk root turns an abstract coordinate into a landmark you can find again from memory — the instruction and the location are the same words.
A Station on the Stomach Channel’s Descent
The site’s own registry sums up the stomach channel in a sentence: it runs down the front of the body from face to second toe, and classical practice reaches for it in matters of digestion, energy, and appetite. Classical texts elaborate the journey’s early chapters — beginning beside the nose, looping through the gum and lip territory of the lower face, climbing to the forehead along the hairline, then descending past the jaw and down the side of the throat. From the region of the collarbone the visible pathway steps onto the front of the chest, and the chest is where Rugen keeps its station.
Read as a sequence of stair-steps, the chest stretch is unusually tidy. Every recorded station follows the same four-cun line while descending one intercostal space at a time, from Qihu under the middle of the collarbone to Rugen in the fifth space. Station eighteen closes the chest chapter: below it the record resumes in the upper abdomen, where Burong (ST19) sits six cun above the navel but only two cun lateral to the midline — the line drawing inward as the channel leaves the ribs behind. The numbering itself tells the story of a long journey passing through, not lingering.
Why does a point on the stomach channel carry such a breast-and-chest portfolio? The traditional answer is the channel map itself. In classical practice any station along a channel could be reached for complaints arising along that channel’s course, and the stomach channel threads precisely the chest-wall territory where the breast sits — classical writers treated the breast region as country this pathway passes through on its long descent. The reasoning traces lines of influence along routes rather than organs in isolation. As a framework it is internally coherent, and it explains why breath and chest entries stand beside the breast ones in the old records.
Traditional Indications, Explained
The dataset records six traditional indications: breast abscess and breast lumps, insufficient lactation, cough, shortness of breath, hiccups, and chest pain. Framed as history rather than promise, these are the complaints classical practice traditionally reached for Rugen over. The breast entries dominate, and they arrive in historical vocabulary: what the old records called an abscess of the breast described an acute, hot, painful swelling, while “breast lumps” gathered palpable masses grouped by how they felt. A modern reader should hear those entries carefully: any new lump, persistent swelling, skin change, discharge, or hot painful swelling of the breast today belongs promptly with a physician — a historic indication is not a licence for home diagnosis.
Insufficient lactation records the tradition’s attention to nursing mothers whose milk flow seemed scanty; it is presented here as cultural history, and readers who are nursing should bring feeding difficulties to qualified clinicians or lactation professionals rather than attempt to manage them alone. Hiccups look like an outlier until the traditional frame is restored: classical teaching described hiccups as the qi of the stomach rebelling upward — counterflow — and a chest-wall station belonging to the stomach channel fits that map neatly. This is general classical context, offered for understanding rather than asserted as mechanism.
Cough and shortness of breath form the familiar breath-family cluster that gathers wherever a channel passes the chest, and the chest-pain entry in the old records usually refers to dull, blocked sensations described alongside fullness — not sudden severe pain, which has always belonged to urgent medical care. It bears repeating plainly: these are the traditional uses recorded in a licensed dataset, offered for cultural and historical understanding. They are not claims that pressing this point treats disease. Where modern research touches self-applied pressure at all, reviews suggest effects are modest and context-dependent, and evidence specific to any single point remains thin.
Self-Care Acupressure at Home
With the point found by the walkthrough above, settle into position: seated, spine tall but unforced, shoulders heavy. Curl your index and middle fingers together and rest the pads — never the tips — on the spot. Begin with contact alone for a few slow breaths, then add small, unhurried circles, letting the skin glide over the tissue beneath rather than grinding against the ribs. Pressure should register as pleasant dullness or mild warmth, never sharpness. A common home rhythm is one to three minutes per side, once or twice daily; finish one side, then give the other the same minutes so the session stays symmetrical.
Quality matters more than duration. Light, patient, regularly repeated contact fits the wellness register this page practises; hard jabbing causes harm and teaches the body nothing. Use finger pads only — never elbows, knuckles, or tools — and warm cold hands before starting, because chilled muscle guards. Choose a quiet corner over a screen and let the practice double as a breathing pause: inhale through the nose, feel the chest rise under still fingers, press gently on the long exhale. Many people anchor the routine to an existing habit — morning washing, an evening wind-down — because consistency, not intensity, is what self-care traditions actually ask for.
Treat the exercise as a small ceremony of attention rather than a treatment session. Across weeks you may notice the area feels less guarded, that breathing feels smoother while you press, or simply that you spent ninety seconds attending to your own body — every one of those outcomes fits the honest scope of self-acupressure. What does not fit is escalation: pressing harder, longer, or deeper to force a result. When curiosity pulls that way, return to gentleness, or simply stop for the day and let tomorrow’s minute be enough.
Cautions and Safe Practice
This point earns more respect than most, and the reason stands written in the licensed record. The dataset instructs practitioners not to needle deeply and to avoid any direction into the chest cavity. The caution follows from plain geography: the lungs fill the chest behind the ribs, and along this stretch of chest wall only muscle and thin membrane separate the skin from structures that must never meet force. Professional training manages that margin with exact technique learned over years; home self-care manages it differently and far more simply — by never leaving the surface at all.
For fingertip acupressure the rules follow from that picture. Keep pressure light and strictly superficial — the intention stays in skin and superficial tissue, never driven inward between the ribs or angled toward the chest. Use pads, never tips, knuckles, elbows, or tools. Skip the point entirely during any acute breathing difficulty, during feverish illness, and over broken or irritated skin — including any cracked, sore, or inflamed skin around the nipple and areola. Wait for a clinician’s clearance after recent chest surgery or injury. Sharp, electric, or radiating sensation means stop at once and do not try again that day. Pregnant readers should consult a qualified practitioner before adding any new point practice, and readers who are nursing should do likewise.
And the wider rule stands over everything: this page is educational, and acupressure is self-care, not diagnosis or therapy. Seek prompt medical attention — not a pressure routine — for a new lump in the breast, skin dimpling or discharge, hot painful swelling with fever, breathlessness at rest or on mild effort, chest pain, coughing blood, a cough lasting beyond a few weeks, or any symptom that frightens you. Persistent complaints belong with a licensed practitioner, medical or East Asian medical as suits the situation. The root imagery is gentle, but the safest gift Rugen offers most people is a calmer, better-informed acquaintance with their own chest wall — touched kindly, and touched lightly.
Rugen, the Milk Root, sits low on the chest where the breast settles onto the chest wall, one intercostal space directly below the nipple. Classical practice reached for it amid breast complaints, scant milk flow, cough, hiccups, and chest pain. This guide walks through finding it by touch, reading its name, and pressing gently and safely.
Cautions from the classical sources
- Keep insertion shallow and never angle into the chest cavity.
Self-care limits
Frequently asked
- How do I find Rugen without knowing anything about cun?
- Use the nipple as the whole map. Find its centre, then slide straight down the chest wall until your fingertips settle into the next groove between ribs — the hollow where the breast meets the chest wall. That groove-level spot is the location the dataset describes. The four-cun figure simply records that the nipple line already marks the right horizontal position, so the downward measurement does the rest.
- Is pressing Rugen myself actually safe?
- Gentle fingertip pressure held on the surface is generally reasonable self-care for healthy adults, because it engages skin and superficial tissue far short of the structures the dataset warns about. The recorded danger concerns deep techniques directed into the chest cavity — a category home acupressure never approaches. Respect the stop signals: sharp pain, radiating sensation, or discomfort that worsens all mean finish immediately.
- What did classical practice use Rugen for?
- The traditional record lists breast abscesses and lumps, insufficient lactation, cough, shortness of breath, hiccups, and chest pain. The breast-heavy portfolio follows from the point’s own address and from the channel that passes there. These are traditional frameworks for understanding the body, documented for cultural context — not evidence-backed treatment claims.
- Why does a stomach-channel point sit on the chest?
- Because the channel’s recorded route passes that way. Classical texts describe it beginning beside the nose, descending the throat, crossing the collarbone region onto the chest — where its stations step down the four-cun line one intercostal space at a time — and continuing to the abdomen and leg. Tradition reaches for stations along a channel for complaints arising along its course, which is why breath and chest entries stand beside the breast ones in Rugen’s records.
- I have noticed a lump in my breast. Should I massage it?
- No. Any new lump, persistent swelling, skin change, or discharge in the breast needs proper clinical assessment promptly. Leave the area entirely alone until a physician has examined it, and mention anything else you have noticed — skin changes, discharge, fever — at the same visit. The old records’ vocabulary about breast lumps belongs to history, not to home diagnosis.
Sources
- 01WHO Standard Acupuncture Point Locations in the Western Pacific Region (2008), World Health Organization — nomenclature conventions.
- 02A Manual of Acupuncture, Peter Deadman, Mazin Al-Khafaji and Kevin Baker — point-name tradition and channel context.
- 03aijiu-mpvue (MIT License) licensed dataset, entry for ST18 Rugen — location, actions, and caution record.
Last reviewed
牌記This leaf, for machines
Old books ended with a colophon saying who printed them. Every leaf here carries the same facts as structured data for agents and search, with no layout in the way.
- GET /en/points/st18/leaf.json
- GET /zh-hant/points/st18/leaf.json
- GET /zh-cn/points/st18/leaf.json
- /llms.txt — the index of every leaf
- JSON-LD in the page: MedicalWebPage, MedicalEntity and FAQPage
{
"id": "ST18",
"name": {
"en": "Rugen",
"gloss": "Milk Root",
"zh-Hant": "乳根",
"zh-Hans": "乳根"
},
"channel": {
"id": "ST",
"order": 18,
"of": 45
},
"location": {
"text": "Directly below the nipple, at the root of the breast, in the fifth gap between the ribs."
},
"for": [
"low milk supply",
"cough",
"chest pain"
],
"press": {
"text": "Gentle pressure, about a minute each side.",
"seconds": 60,
"sides": "both"
},
"cautions": [
"Not over a breast lump, redness or warmth; have a doctor check it."
],
"source": "Zhenjiu Jiayi Jing, book 3",
"url": "https://acupoints.com/en/points/st18",
"lastReviewed": "2026-08-24"
}