The point of the anguished cry. Yixi (BL-45) sits on the outer Bladder channel beside the Heart's back-shu point, and its very name captures a sound of pain or sudden distress. It opens the chest, eases breathing, and moves Qi through a tight, suffering back — a point that listens to the body's cry and helps it release.
Name & story
The name 譩譆 Yixi is quite remarkable — it is written with characters that imitate a sound, the involuntary exclamation a person makes when they are in sharp pain or great distress: something like "ah!" or "oh!" In the old tradition, it was said that when you press this point on someone who is suffering, they cry out — and that cry is the point's own name. It is one of the rare acupoints in Chinese medicine named not for a place or an image, but for the living sound of the body in pain. That alone tells you something about its character: it touches deep suffering, opens what is locked, and gives the body a way to let go.
Point family & character
Yixi (BL-45) belongs to the Bladder Meridian (BL), specifically on the outer, lateral line of back points. It lies at the level of BL-15 (Xinshu), the back-shu point of the Heart, and is considered the outer Bladder channel point corresponding to that level. According to the Essential Questions (Suwen), the five outer Bladder channel points level with the five zang back-shu points — including BL-45 — share the action of draining Heat from the corresponding zang organ.
Five-element dynamics
The outer Bladder channel back points carry the energy of the inner channel but in a subtler, more expansive way. BL-45 sits beside Xinshu BL-15, the Heart's back-shu point — the place where the Heart's Qi is infused into the back. The Heart governs the Shen and the Blood (Xue), and its channel opens into the chest. When Heat builds in the chest, or when Qi rebels upward and breathing becomes laboured, this outer point helps drain that excess and restore the smooth downward flow of Lung and Heart Qi. Its name — a cry of pain — also hints at its ability to release what has been suppressed or locked in.
Location
BL-45 is found on the back, 3 Cun lateral to the lower edge of the spinous process of the fifth thoracic vertebra (T5) — that is, 3 Cun from the midline, directly lateral to Xinshu BL-15. It lies on the outer Bladder line, one level lateral to BL-15.
Anatomy & fascia
The point lies in the region of the thoracic back muscles, in the lateral part of the back at the level of the fifth thoracic vertebra (T5).
Needling
The golden tip
If you experience tightness or aching in the mid-upper back, or a sense of the chest being locked, a warm compress or gentle massage along the outer Bladder line of the thoracic back — the area roughly 3 Cun from the spine on either side at mid-back level — can help ease that constriction. Because the point is on the back, self-massage is best done with a partner, or by leaning gently against a massage ball placed against the wall at this level.
For education only — not medical advice. Consult a qualified practitioner.