Stomach MeridianST18

Rugen 乳根

For reference only · not a substitute for diagnosis or treatment

Short answer

4 B-cun out from the front midline, in the gap below the fifth rib (fifth intercostal space).

See it in 3DRotate the body and peel back the skin to see the bones and muscles beneath.
Open the 3D Acupoint Map →

🖼See it in pictures

Rugen — ① Where on the body? — **① Where on the body?**

Rugen — Textbook view — skin on the left, muscle and bone underneath on the right — **Textbook view — skin on the left, muscle and bone underneath on the right**
Location and structures come from our 3D model; only the drawing style was refined with AI. Labels are added by us.

Rugen — ③ Under the skin — **③ Under the skin**
Sternocostal head of pectoralis major muscle · Internal intercostal muscles · Costal cartilage of fifth rib

Rendered straight from the 3D model at the computed location. The glowing ring marks Rugen.

On this page

Where is Rugen?
How do I find it on my body?
Before you press
How has it been used traditionally?
FAQ

1Where is Rugen?

4 B-cun out from the front midline, in the gap below the fifth rib (fifth intercostal space).

In men it is on the nipple line; in women, at the middle of the fold under the breast.

It is on the front chest.

Beneath the point

Sternocostal head of pectoralis major muscle · Internal intercostal muscles · Costal cartilage of fifth rib

Our 3D measurement · In our 3D model: chest skin at the fifth intercostal space, re-read at the 4-cun line (83.2 mm from the front midline).

2How do I find it on my body?

Men: from the nipple (fourth space), move down one rib to the next gap on the nipple line.
Women: take the middle of the crease beneath the breast.

Check · the fifth intercostal space, on the 4 B-cun line.

What is a “cun”?

A cun is a body-scaled unit of length. The precise way is to divide a bone length into equal parts (proportional bone cun); finger widths are a quick estimate.

📖 Words explained

sternocostal head of pectoralis major: The large middle part of pectoralis major, starting from the breastbone and upper rib cartilages. It pulls the arm in toward the body.
intercostal space: The gap between two ribs, felt with a fingertip as a slight groove between bone and bone. It is named after the rib above it (the gap below the first rib is the first intercostal space).
internal intercostal muscles: The layer of thin rib-gap muscles just inside the external intercostals. They help lower the ribs when you breathe out hard.
costal cartilage: The firm cartilage that joins the front end of a rib to the breastbone. It is a little softer and more bendy than bone, so the chest can expand when we breathe.
chest wall: The wall around the chest organs, made of skin, muscle, ribs and the muscles between them. In places it is thinner than you might think.

3Before you press

⚠ Do not press when

The pleura and lung lie just beneath the chest wall here.
Do not jab with pointed tools or dig in deeply.
Sudden breathlessness or chest pain is an emergency — call emergency services; do not try acupressure.
If you notice a new lump, pain or discharge in the breast, see a doctor first rather than pressing.
Avoid broken or swollen skin and press only to a comfortable level.
Acupressure is not a substitute for medical care.

4How has it been used traditionally?

The name joins ru (breast) and gen (root): the root of the breast. WHO gives separate locating cues for men and women.

From traditional texts — not a claim of effect.

?FAQ

Where exactly is Rugen?

4 B-cun out from the front midline, in the gap below the fifth rib (fifth intercostal space). In men it is on the nipple line; in women, at the middle of the fold under the breast. It is on the front chest.

How do I find Rugen?

Men: from the nipple (fourth space), move down one rib to the next gap on the nipple line. Women: take the middle of the crease beneath the breast. the fifth intercostal space, on the 4 B-cun line.

What should I watch out for?

The pleura and lung lie just beneath the chest wall here. Do not jab with pointed tools or dig in deeply. Sudden breathlessness or chest pain is an emergency — call emergency services; do not try acupressure. If you notice a new lump, pain or discharge in the breast, see a doctor first rather than pressing. Avoid broken or swollen skin and press only to a comfortable level. Acupressure is not a substitute for medical care.

← PreviousRuzhong · ST17 Next →Burong · ST19

Sources

Location: WHO Standard Acupuncture Point Locations in the Western Pacific Region (2008), p. 54
Standard comparison: Chinese national standard GB/T 12346-2021 (Nomenclature and location of meridian points)
Korean anatomical terms and locating tips: KMCRIC Standard Acupoint DB (Korea)
Classification cross-check: AcuAtlas dataset (CC BY 4.0)
Safety: Chinese Medicine Council of New Zealand, Safety in Clinical Practice Guidance (2023)

Positions computed from the WHO standard locations (2008) on Z-Anatomy (CC BY-SA 4.0) · BodyParts3D © DBCLS. For reference only — not a substitute for diagnosis or treatment. See a clinician if you are unwell.