Mu Tong (木通) — Akebia Stem | TCM Herb Guide

At a Glance

• Herb: Mu Tong
• Chinese name: 木通 (Mù Tōng)
• Latin name: Akebiae Caulis
• Nature: Cold
• Taste: Bitter
• Meridian: Heart / Small Intestine / Bladder
• Category: Herbs that Drain Dampness (Diuretic Herbs)
• Introduction: Mu Tong (木通), Caulis Akebiae, is the dried stem of Akebia quinata or A. trifoliata (Chuan Mu Tong). A key herb to clear heart fire and drain it through the small intestine and bladder, it promotes urination, unblocks channels, and promotes lactation. Note: Guan Mu Tong (关木通, Aristolochia manshuriensis) contains aristolochic acid and is banned in many countries due to nephrotoxicity — only Chuan Mu Tong or Bai Mu Tong should be used clinically.

Action

• Clears heart fire and drains heat through the small intestine
• Promotes urination and treats dysuria
• Unblocks the channels and collaterals
• Promotes lactation

Clinical Application

• Heart fire transferring to small intestine: mouth sores, dysuria with burning urine — combines with Zhu Ye, Sheng Di Huang, Gan Cao
• Damp-heat in the lower jiao: burning, painful urination, hematuria — combines with Hua Shi, Che Qian Zi, Qu Mai
• Wind-damp bi syndrome with joint pain — combines with Fang Ji, Yi Yi Ren
• Insufficient lactation from qi-blood obstruction — combines with Wang Bu Liu Xing, Tong Cao, Dang Gui

Precautions

• Dosage: 3–6 g in decoction
• CRITICAL: Use only Chuan Mu Tong (川木通, Akebia) or Bai Mu Tong — NOT Guan Mu Tong (关木通, Aristolochia) which causes irreversible kidney failure
• Contraindicated in pregnancy
• Contraindicated in kidney deficiency or yin deficiency without heat
• Use cautiously and at minimum effective dose — Akebia species also have some diuretic force

Formula

• Dao Chi San (导赤散): Mu Tong, Zhu Ye, Sheng Di Huang, Gan Cao — clears heart fire, drains heat via urine
• Ba Zheng San (八正散): Mu Tong, Hua Shi, Qu Mai, Bian Xu, Zhi Zi, Da Huang, Che Qian Zi, Deng Xin Cao, Gan Cao — clears damp-heat, promotes urination for painful dysuria
• Tong Ru Dan (通乳丹): Mu Tong, Wang Bu Liu Xing, Tong Cao, Dang Gui, Zhu Ti — promotes lactation

Combinations

• Akebia Stem (木通) + Fresh Rehmannia Root (生地黄) + Lophatherum Herb (竹叶) → Dao Chi San (导赤散): clear Heart fire, promote urination; mouth sores, dark urine, Heart-Small Intestine fire
• Akebia Stem (木通) + Plantain Seed (车前子) + Talcum (滑石) → clear heat, promote urination; hot lin and dysuria
• Akebia Stem (木通) + Vaccaria Seed (王不留行) + Pangolin Scales (穿山甲) → promote lactation, unblock breast channels; postpartum insufficient milk
• Akebia Stem (木通) + Dianthus Herb (瞿麦) + Common Knotgrass (扁蓄) → clear heat, resolve dampness; urinary tract infection
• Akebia Stem (木通) + Achyranthes Root (牛膝) + Job’s Tears Seed (薏苡仁) → clear lower jiao damp-heat; joint pain and bi syndrome

Pharmacological Effects

• Diuretic
  • increases urine output
• Anti-inflammatory; antibacterial; promotes lactation
  • galactagogue
• Cardioprotective; lowers blood pressure; note: aristolochia manshuriensis
  • 关木通) is nephrotoxic — modern use specifies Akebia trifoliata only

Classic Description

• Shen Nong Ben Cao Jing (《神农本草经》): ‘Governs expelling evil parasites, eliminating Spleen and Stomach cold-heat, unblocking the nine orifices, blood vessels, and joints, and preventing forgetfulness.’
• Ben Cao Gang Mu (《本草纲目》): ‘Akebia Stem: above it unblocks the Heart and clears the Lung, treats headache, and opens the nine orifices; below it drains damp-heat, promotes urination, opens the Large Intestine, and treats contracture pain throughout the body.’
• Ben Cao Bei Yao (《本草备要》): ‘Drains fire, moves water, unblocks the channels, opens orifices; treats the five stranguries and floating edema.’
• Yao Xing Lun (《药性论》): ‘Treats the five stranguries, promotes urination, opens pass-gate blockage, treats excessive sleepiness, treats water edema, and eliminates vexation heat.’