Sang Zhi (桑枝) — TCM Mulberry Twig for Upper Limb Bi-Syndrome

At a Glance

• Herb: Sang Zhi
• Chinese name: 桑枝 (Sāng Zhī)
• Latin name: Mori Ramulus
• Nature: Neutral
• Taste: Bitter
• Meridian: Liver
• Category: Herbs that Expel Wind-Dampness
• Introduction: Sang Zhi (Ramulus Mori) is the young twig of the white mulberry tree (Morus alba), harvested in late spring and early summer before the leaves fully mature. First recorded in the Song dynasty Ben Cao Tu Jing, this mild and slightly bitter herb is distinguished by its affinity for the extremities, particularly the shoulder girdle and upper limbs. Modern phytochemical analysis reveals oxyresveratrol, flavonoids, and mulberroside compounds with anti-inflammatory and urate-lowering effects, supporting its potential use in gout management alongside rheumatic conditions. Its gentle and non-drying nature makes it suitable for long-term use in chronic joint complaints.

Action

• Dispels Wind-Damp and unblocks the channels, with special affinity for the upper limbs and shoulders
• Reduces joint swelling and stiffness from Wind-Damp obstruction
• Promotes circulation in the extremities to relieve numbness

Clinical Application

• Bi-syndrome with pain, stiffness, and difficulty moving the shoulders, elbows, wrists, and fingers
• Numbness and weakness of the upper extremities from Wind-Damp obstruction
• Limb edema with mild Wind-Damp involvement
• Suitable as a guiding herb (yin jing yao) to direct formulas to the upper body and arms

Precautions

• Dose: 9–15 g in decoction; up to 30 g for severe or chronic cases
• Generally safe and mild; well tolerated with long-term use
• Primarily indicated for Wind-Damp with some heat element; warmer herbs (e.g., Gui Zhi) more appropriate for pure Cold Bi-syndrome
• No significant contraindications reported; safe in combination formulas

Formula

• Sang Zhi Gao (桑枝膏) — concentrated Sang Zhi decoction taken alone as a syrup for chronic joint pain (classical single-herb preparation)
• Combined with Gui Zhi for Wind-Cold shoulder pain and restricted arm movement
• Combined with Si Gua Luo and Ji Xue Teng for upper limb numbness and poor circulation
• Combined with Sang Ji Sheng for comprehensive limb Bi-syndrome affecting both upper and lower extremities

Combinations

• Mulberry Twig (桑枝) + Clematis Root (威灵仙) + Saposhnikovia Root (防风) → expel wind-damp, unblock the channels; upper limb bi syndrome and shoulder and arm pain
• Mulberry Twig (桑枝) + Mulberry Mistletoe (桑寄生) + Pubescent Angelica Root (独活) → expel wind-damp, tonify the Liver and Kidney; chronic lower limb and lower back bi syndrome

Pharmacological Effects

• Anti-inflammatory
  • flavonoids — inhibit COX and inflammatory cytokines
• Analgesic; antidiabetic
  • DNJ — inhibits alpha-glucosidase, lowers blood sugar
• Antioxidant
  • oxyresveratrol — strong free-radical scavenger
• antihypertensive; antiviral; antimicrobial; especially targeted at UPPER LIMB bi syndrome — twig form enters arm and shoulder channels

Classic Description

• Ben Cao Tu Jing (《本草图经》): ‘Treats generalized wind itching and dryness, beriberi with wind qi, limb cramping, counterflow qi, eye dizziness, Lung qi cough, and disperses food; promotes urination; also treats dry mouth.’
• Ben Cao Gang Mu (《本草纲目》): ‘Mulberry Twig benefits the joints, nourishes fluids, moves water and expels wind; its function surpasses that of Mulberry Leaf.’
• Ben Cao Bei Yao (《本草备要》): ‘Benefits the joints, expels wind-damp, nourishes fluids; also treats hand and foot cramping and wind-damp painful impediment; especially effective for upper limb painful impediment.’