Bladder Meridian
The longest meridian: two parallel lines down the entire back, with 67 classical points.
Pathway
The Bladder meridian begins at the inner canthus of the eye at BL-1 Jingming, ascends the forehead, and crosses the vertex. A branch enters the brain; the main line descends the posterior neck and back in two parallel columns, one 1.5 cun and one 3 cun from the midline, passing the back-shu points associated with each organ.
Below the waist it continues through the buttock and posterior thigh, passes the popliteal fossa at BL-40 Weizhong, descends the calf, and ends at the lateral side of the little toe at BL-67 Zhiyin. With 67 points, it is the longest and most densely populated meridian.
Role in TCM theory
- The body's longest channel — Its two back lines carry the back-shu points, where the tradition accesses each organ. This is why so much back work in TCM begins on the bladder line.
- Water pair with the Kidney — Bladder and kidney share the Water element; the bladder is described as the "official of the region" that stores and releases fluids under the kidney's direction.
- The defensive surface — The outer bladder line is associated with wei qi and the body's response to cold and wind.
- A channel of the whole back — From the crown to the little toe, its pathway makes it central to traditional work on the spine, back, and posterior legs.
Common acupoints on the Bladder meridian
| Point | Name | Location | Traditional use |
|---|---|---|---|
| BL-1 | Jingming (睛明) | In the depression between the inner canthus and the eyeball | The first point; classically associated with the eyes. Press only very gently. |
| BL-23 | Shenshu (腎俞) | On the lower back, 1.5 cun lateral to the lower border of the spinous process of L2 | The back-shu point of the kidney; traditionally used to support kidney qi |
| BL-40 | Weizhong (委中) | At the midpoint of the popliteal crease | The he-sea point; classically used for low back and knee patterns |
| BL-57 | Chengshan (承山) | In the depression at the lower end of the gastrocnemius, when the heel is lifted | Traditionally used for calf tightness |
Point locations follow the WHO Standard Acupuncture Nomenclature (1991). Gentle acupressure is generally considered low-risk; needling must only be performed by a licensed practitioner.
The 3–5 pm window
3–5 pm is the bladder's peak. Traditional advice favors drinking water and taking a short break; it is also a common window for afternoon movement or a walk.
How this is viewed today
BL-23 and BL-40 are frequently used in trials for low back pain; systematic reviews report modest short-term effects and call for better-designed studies. Seek medical evaluation for back pain with weakness, numbness, or loss of bladder control.
Sources & further reading
- Huangdi Neijing (黃帝內經), c. 2nd century BCE.
- Nanjing (難經), c. 1st–2nd century CE.
- World Health Organization, Standard Acupuncture Nomenclature, 2nd ed., 1991.
- Deadman P, Al-Khafaji M, Baker K. A Manual of Acupuncture. Journal of Chinese Medicine Publications.
- National Center for Complementary and Integrative Health, Acupuncture: What You Need To Know.
Related: Kidney meridian · Small Intestine meridian · Body clock · all twelve meridians