B 28, also known as Bladder Shu or Pangguangshu, is an essential back-shu point on the Bladder meridian. Located in the lower back region, this point corresponds with the urinary bladder organ system in Traditional Chinese Medicine (TCM) and plays a significant role in relieving lumbar pain and regulating bladder function.
Main therapeutic applications include:
- Lower back pain and sacral tension
- Urinary disorders, such as frequent urination or retention
- Pelvic congestion and reproductive system imbalance
Alternate names: Pangguangshu (B 28), BL 28, Urinary Bladder 28.
Summary Table
| Attribute | Details |
|---|---|
| Pressure Point Name | Bladder Shu – B 28 (Pangguangshu) |
| Body Area | Lower Back |
| Exact Location | 1.5 finger widths lateral to the midline at the level of the sacrum |
| Common Uses | Lower back pain, bladder dysfunction, pelvic stagnation |
| Stimulation Technique | Firm fingertip or knuckle pressure, 1–2 minutes per side |
| Contraindications | Avoid over active inflammation or during pregnancy |
Clinical Significance & Associated Conditions
B 28 is commonly used in clinical acupressure and acupuncture settings to address:
- Chronic lower back pain and sacroiliac dysfunction
- Urinary frequency, incontinence, or retention
- Menstrual cramps and pelvic stagnation
- Lumbar stiffness due to kidney deficiency or cold invasion
It is a Back-Shu point—a category of points in TCM that correspond to internal organs—and thus carries strong regulatory effects on the urinary and reproductive systems.
Location
B 28 is located on the lower back, at the level of the second posterior sacral foramen:
- Find the midline of the sacrum at the level of the dimples above the buttocks.
- From this central point, move 1.5 finger widths laterally (approximately 3–4 cm) on either side.
The point is often palpated as a slight depression in the sacral region and may feel tender to the touch.
Looking for an easier way to use this point in your wellness routine?
This pressure point is simple to locate and even easier to apply when guided step-by-step. It’s featured in over 70 evidence-based pressure point protocols inside our Pressure Points Guide app. Whether you’re looking to relieve lower back tension, improve urinary function, or ease pelvic discomfort, the app guides you through every session with visuals and audio. Click here to download our app.
How to Stimulate It
- Tool: Use thumbs, knuckles, or a massage ball.
- Technique: Apply firm, vertical pressure with gentle circular motion.
- Duration: 1 to 2 minutes per side, or longer in chronic conditions.
- Posture: Lie face-down or stand with support against a wall.
- Frequency: Daily or 3–5 times per week for chronic lower back issues.
- Can be paired with: B 23 (Kidney Shu) and B 32 for reproductive and urinary balance.
Benefits and Common Uses
Bladder Shu is recognized for its influence on both physical and internal systems:
- Musculoskeletal: Eases chronic lumbar pain, stiffness, and sacral tension
- Urinary system: Regulates bladder function and supports elimination
- Reproductive health: Assists with menstrual cramps and pelvic qi stagnation
- Energetics: Tonifies the Kidney and Bladder systems; disperses damp-cold in the lower jiao
In cases of cold invasion or qi stagnation, this point is often combined with moxibustion to warm and activate local circulation.
Physiological Functions & Mechanisms
From an anatomical standpoint, B 28 overlies the sacroiliac joint, influencing surrounding muscles such as the gluteus medius, piriformis, and erector spinae. Stimulation of this point may:
- Enhance pelvic floor nerve conductivity
- Reduce muscle tension in the lumbar and sacral region
- Activate visceral reflex arcs impacting the bladder and reproductive organs
TCM theory holds that B 28 governs the water pathways and supports descending and draining functions of the Bladder.
Practitioner Insight
Bladder Shu is one of the first points I consider for clients with chronic low back tension that seems to linger or feel “deep and dull.” It’s especially helpful for cases where physical tension is accompanied by urinary or cycle irregularities. I often combine it with guided breathwork or abdominal massage to support fluid regulation and lower body flow.
Safety & Contraindications
- Avoid use over open wounds, bruising, or acute sacral inflammation.
- Contraindicated during pregnancy due to its influence on the uterus and pelvic floor.
- Adjust pressure in those with osteoporosis, spinal disc injury, or sensitivity in the sacral area.
Explore more in our acupressure safety guide and full acupressure article collection.
As always, listen to your body and stop if discomfort arises.
Related Points & Techniques
Complementary Points:
Adjunct Techniques:
- Gentle lower back stretching (cat-cow, pelvic tilts)
- Use of warming compresses or moxa therapy
- Abdominal and hip acupressure to support downward qi flow
More sessions with Bladder Shu (B 28) in our Pressure Points Guide App
Scientific Perspective
While research specific to B 28 is limited, broader studies on sacral acupoints suggest benefits for chronic low back pain, urinary urgency, and dysmenorrhea. Functional MRI has shown that pressure on bladder-associated back-shu points activates areas of the brain involved in bladder control and pain modulation. Clinical trials also support combining this point with B 23 for chronic lumbar support and pelvic floor stabilization.