俠白 Xiabai
“Flanking White” · LU4
Hand Taiyin · 4 of 11
Where. On the inner upper arm, at the outer edge of the biceps, one thumb-width below LU3.
For. Cough, dry retching, an aching upper arm.
Press. Firm thumb pressure, about a minute, then the other arm.
俠白，在天府下，去肘五寸動脈中按 · Press with me
Six slow breaths
About a minute. Press as you breathe out, ease as you breathe in.
鄰 · Neighbouring leaves
First, the map: where LU4 sits along the lung channel
The lung channel begins high on the chest and flows outward and downward along the front of the shoulder, then down the soft inner face of the upper arm, across the elbow crease, through the forearm, and out to the thumb. Its eleven classical points are numbered in the order the channel travels, so the low numbers live near the shoulder and armpit while the high numbers arrive at the wrist and hand. LU4 belongs to that quiet stretch of inner upper arm — above the busy elbow region marked by Chize (LU5) and below Tianfu (LU3), which nestles close to the armpit.
That placement matters for how the point is understood. Points on the upper reaches of a limb channel were traditionally read as speaking to the deeper trunk — the chest, the lungs, the diaphragm region — while still remaining reachable for purely local complaints such as a sore upper arm. Xiabai therefore wears two hats at once in classical listings: a distant helper for chest and breathing concerns, and a nearby one for the very muscles it rests against. Holding both readings makes the rest of this guide easier to follow.
Finding Xiabai by touch, step by step
Sit comfortably and let your left arm hang loose or rest across your lap, palm turned forward. Look at the inner surface of the upper arm and squeeze gently: the rounded belly of the biceps rises under your fingers, carrying a firm ridge along its outer-facing edge on the thumb side. The catalogue locates Xiabai on the medial aspect of the arm, on the radial border of biceps brachii — in everyday terms, on the inner arm, right along that muscular edge.
To pin down the height, use the elbow crease as your anchor. Traditional measurement divides the inner arm from cubital crease to the front of the armpit into nine equal parts called cun — proportional units taken from your own body rather than from a ruler. Xiabai sits five of those parts above the crease, a little past halfway up toward the armpit; measured from above, the same spot lies four parts below the front fold of the armpit. Both descriptions land in one place. Press around that neighborhood until you find a tender, slightly dense spot in the groove hugging the biceps edge — that confirmable soreness is the usual signature of the point.
Reading the name: xia, bai, and flanking white
Chinese point names compress imagery into two or three characters, and Xiabai rewards a slow read. Bai, white, is the colour the five-phase tradition assigns to the lungs and to metal: autumn light, clarity, crisp dry air — and the pale complexion classical writers watched for in lung disorders. Naming a lung-channel point white ties it visibly, from the first character onward, to the organ it serves.
Xia is the livelier character. Commentaries gathered in A Manual of Acupuncture read it as escort, guardian, or flanking companion: the point stands guard beside the whiteness of the lung qi, like an aide walking alongside a pale banner. Other glosses link xia phonetically to jia, to flank, which suits the anatomy neatly — Xiabai truly stands beside the whitish sheen of the biceps and its tendon on the inner arm. Whichever layer you favour, the name keeps pointing at one picture: a modest sentinel posted next to something luminous, high on the inner arm where the lung channel gathers itself for the journey down.
What tradition reaches for at Xiabai
The compiled catalogue lists five classical actions for Xiabai: cough, asthma, dry retching, upper arm pain, and rapid heartbeat. Read with traditional-use framing rather than as modern claims, these are the situations in which classical practice historically reached for this point — a record of where earlier practitioners found it useful, passed down through the literature rather than tested in contemporary trials.
The chest-related entries fit the point’s channel position. Because the lung channel descends from the chest along exactly this corridor of the inner arm, a point here was treated as a downstream doorway toward the lung itself: cough and wheezing breath, the most repeated lung-channel entries, sit in Xiabai’s listing alongside those of its neighbors. Dry retching reads differently — it belongs to the stomach rebelling upward — and classical listings often pair lung-channel points with such counterflow, reflecting the traditional view that the lung’s descending quality helps settle what the stomach sends upward. Rapid heartbeat extends the same settling logic toward the chest as a whole. Upper arm pain is finally the plainly local entry: a point lying on the radial border of the biceps was reached for in classical practice for aching in precisely that region. None of this amounts to a modern evidence statement; it is the traditional map, faithfully reported, and the shared safety note on every page of this site applies in full.
Gentle self-acupressure at home
Self-acupressure at Xiabai asks for less force than you probably expect. Sit upright in a chair, shoulders easy, and support the working arm across a cushion or your opposite forearm so the inner arm faces up. Locate the point with a fingertip first, then settle your thumb pad onto it. Begin with light contact and let the pressure grow over a few slow breaths until you reach a firm-but-comfortable depth — enough to feel a spreading ache, never enough to make yourself flinch.
From there, work in small, unhurried circles, keeping the pressure even, and let your breathing stay slower than conversation. One to two minutes per side is plenty for a first session; many people simply repeat it morning and evening on days they feel they want it. If one side feels markedly more tender than the other, give the tender side the gentler treatment rather than the harder one. Between sessions, loose fisted tapping along the inner arm, armpit toward elbow, offers a lighter alternative some people enjoy. Stop at once if anything sharpens into true pain, and skip the work entirely over broken, inflamed, or freshly bruised skin. Acupressure here is self-care, not treatment: it complements, and never replaces, advice from a qualified clinician.
Cautions, limits, and honest boundaries
The catalogue entry for Xiabai records no point-specific cautions, and this page echoes that emptiness deliberately rather than inventing warnings the dataset does not carry. The absence is not a blank cheque: it means no classical restriction was transmitted for this point, while the universal rules of safe self-care still govern everything above. Pressure stays moderate, sessions stay short, and sharp sensation ends the session immediately.
Some situations belong with professionals, full stop. Persistent or worsening cough, breathlessness that arrives uninvited, chest pain, palpitations that feel new or frightening, vomiting that will not settle — these deserve assessment by a physician or licensed acupuncture practitioner, not a longer session with your thumb. If you are pregnant, managing a chronic condition, or taking blood-thinning medication, ask a qualified practitioner before adding any new point work. Deeper professional techniques at this point — including needling, which requires licensed training and is never part of self-care — fall entirely outside what this page teaches. What remains is simple: a quiet point on the inner arm, a few minutes of patient pressure, and the good sense to hand over whatever self-care cannot address.
Xiabai — the fourth point of the lung channel — rests high on the soft inner side of the upper arm. Classical practice reaches for it when cough, labored breathing, queasiness, or a worn-out arm calls for a calm touch. Learn to find it, read its name, and press it gently at home.
Self-care limits
Frequently asked
- Is Xiabai hard to find on my own arm?
- Most people find it within a minute or two once they know two landmarks: the biceps edge and the halfway mark of the inner upper arm. Slide your fingers along the radial border of the biceps upward from the elbow crease, past the midpoint, and press gently until you meet a distinct tender spot in the groove beside the muscle. That soreness confirms you are in the right place, and it usually grows more obvious with a little practice.
- How long and how often should I press the point?
- One to two minutes per side, once or twice a day, is a comfortable rhythm for self-care. Let the pressure build gradually, keep it at a level you could happily sustain while reading, and stop the moment anything turns sharp. On days you feel no particular need, skipping entirely is perfectly fine — consistency over weeks matters far more than intensity in any single sitting.
- Can pressing LU4 ease a cough straight away?
- Tradition reaches for Xiabai in patterns involving cough, and some people find calm, unhurried pressure here pleasantly settling while a cough runs its course. That is a traditional-use statement, not a promise of effect, and self-acupressure is a comfort measure rather than a treatment. If a cough persists beyond a couple of weeks, worsens, or arrives with fever or breathlessness, the responsible next step is a healthcare professional, not more pressure.
- Why does the point feel tender or achy when pressed?
- A spreading, mildly sore fullness under the thumb is the sensation people most often report at channel points, and at Xiabai it tends to gather right along the biceps border where the tissue runs denser. Practitioners have long treated that arriving ache as a sign the location is correct. Treat it as feedback about depth, not a goal in itself: comfortable ache is welcome, while genuine pain means you have gone past useful and should ease off.
- Can I pair Xiabai with breathing exercises?
- Yes, and many people find the pairing natural. Slow nasal breathing — a lengthened exhale in particular — settles nicely alongside steady pressure on a lung-channel point, and doing both together turns a minute of acupressure into a brief pause rather than a chore. Keep the sequence simple: find the point, begin the circles, lengthen the exhale, finish with a slow release and a moment of stillness.
- Who should leave this point alone or seek advice first?
- Anyone who is pregnant, anyone on blood-thinning medication, and anyone managing a chronic respiratory or cardiac condition should check with a qualified practitioner before adding point work. Skip the area entirely if the skin there is broken, inflamed, freshly bruised, or recovering from an injection or vaccination in the arm. And if symptoms the point is traditionally associated with — cough, breathlessness, palpitations — are severe, sudden, or stubbornly persistent, let a professional take the lead.
Sources
- 01aijiu-mpvue (MIT License), complateXwInfo.json — Chinese-language location, indications, and point class for this entry.
- 02WHO Standard Acupuncture Point Locations in the Western Pacific Region (2008) — nomenclature conventions followed for the English wording.
- 03A Manual of Acupuncture (Deadman et al.) — point-name commentary and channel-context background.
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/lu4/leaf.json
- GET /zh-hant/points/lu4/leaf.json
- GET /zh-cn/points/lu4/leaf.json
- /llms.txt — the index of every leaf
- JSON-LD in the page: MedicalWebPage, MedicalEntity and FAQPage
{
"id": "LU4",
"name": {
"en": "Xiabai",
"gloss": "Flanking White",
"zh-Hant": "俠白",
"zh-Hans": "侠白"
},
"channel": {
"id": "LU",
"order": 4,
"of": 11
},
"location": {
"text": "On the inner upper arm, at the outer edge of the biceps, one thumb-width below LU3."
},
"for": [
"cough",
"dry retching",
"an aching upper arm"
],
"press": {
"text": "Firm thumb pressure, about a minute, then the other arm.",
"seconds": 60,
"sides": "both"
},
"cautions": [],
"source": "Zhenjiu Jiayi Jing, book 3",
"url": "https://acupoints.com/en/points/lu4",
"lastReviewed": "2026-08-24"
}