BL22 Sān Jiāo Shū

Reviewed by · Licensed Acupuncturist & TCM Physician · Last reviewed June 2026

BL22 (Sān Jiāo Shū, “Sān Jiāo Shū”) is the Back-Shu Point point of the Bladder Meridian. It is located on the back, 1.5 cun lateral to the lower border of the spinous process of the first lumbar vertebra (L1). The classics locate this point below the thirteenth vertebra. It regulates the San Jiao, resolves dampness, tonifies the Spleen and Stomach, strengthens the lower back, and dispels pathogenic factors.

Location

On the back, 1.5 cun lateral to the lower border of the spinous process of the first lumbar vertebra (L1). The classics locate this point below the thirteenth vertebra.

Needling

Insert obliquely toward the spine, 0.5 to 1.0 cun. Perpendicular insertion of 1.0 to 1.5 cun is also used, but caution is required to avoid injuring the kidney.

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TCM functions

Regulates the San Jiao, resolves dampness, tonifies the Spleen and Stomach, strengthens the lower back, and dispels pathogenic factors..

Indications

Headache, inability to eat, abdominal pain, desire for diarrhea, abdominal distention, borborygmus, vomiting, diarrhea, undigested food in stool, shoulder and back stiffness, stiff lumbar spine, inability to bend forward or backward, dizziness, emaciation despite eating, urinary disorders, edema, bloody urine, turbid urine, seminal emission, consumptive disease (lao), weakness and emaciation, accumulation and gathering disorders of the five and six Fu-organs, fullness of the heart and abdomen, pain in the lower back and back, vomiting and counterflow, alternating chills and fever, scanty qi, urinary retention, jaundice, dysentery, intestinal rumbling..

Back-Shu Point

Clinical notes

As the Back-Shu point of the San Jiao, this point is fundamental for regulating the transformation and transportation of fluids and food throughout the body. It is classically indicated for a wide range of digestive disorders, from poor appetite and abdominal distention to borborygmus and diarrhea, reflecting its role in harmonizing the Middle and Lower Burners. Its use for edema, urinary issues, and emaciation further highlights its function in managing fluid metabolism and nourishing the body. Additionally, it is a key local point for stiffness and pain of the lumbar spine and back.

On the Bladder channel

BL22 is one of 67 points on the Bladder Meridian. Nearby points:

Frequently asked questions

Where is BL22 located?

BL22 (Sān Jiāo Shū) is located on the back, 1.5 cun lateral to the lower border of the spinous process of the first lumbar vertebra (L1). The classics locate this point below the thirteenth vertebra.

What is BL22 used for?

BL22 regulates the San Jiao, resolves dampness, tonifies the Spleen and Stomach, strengthens the lower back, and dispels pathogenic factors. Common clinical indications include headache, inability to eat, abdominal pain, desire for diarrhea, abdominal distention, borborygmus, vomiting, diarrhea, undigested food in stool, shoulder and back stiffness, stiff lumbar spine, inability to bend forward or backward, dizziness, emaciation despite eating, urinary disorders, edema, bloody urine, turbid urine, seminal emission, consumptive disease (lao), weakness and emaciation, accumulation and gathering disorders of the five and six Fu-organs, fullness of the heart and abdomen, pain in the lower back and back, vomiting and counterflow, alternating chills and fever, scanty qi, urinary retention, jaundice, dysentery, intestinal rumbling.

How is BL22 needled?

Insert obliquely toward the spine, 0.5 to 1.0 cun. Perpendicular insertion of 1.0 to 1.5 cun is also used, but caution is required to avoid injuring the kidney. Caution: Overlies the thoracic cavity — risk of PNEUMOTHORAX. Needle obliquely or transversely, never deeply or perpendicularly toward the chest wall.

Which meridian is BL22 on?

BL22 is a point on the Bladder Meridian (Zú Tài Yáng Páng Guāng Jīng).

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⚠️ This page is for general education and is not medical advice. Acupuncture is a traditional practice; evidence varies by condition and study quality, and individual results differ. It does not replace diagnosis or treatment by a licensed professional. Always consult a qualified acupuncturist or physician.