Natural Herb Library

Oyster Shell

Chinese
牡蛎
Pinyin
Mu Li
Latin
Concha Ostreae
Scientific specimen plate of Oyster Shell, Concha Ostreae, showing rough shell valves, inner shell surfaces, and diagnostic oyster-shell details.
Botanical plate by Kodi .

Known in TCM as Mu Li (牡蛎), this salty and astringent, slightly cold herb enters the Liver and Kidney. Traditionally, it pacifies the Liver and subdues Yang; treats dizziness, tinnitus, headache, and irritability from Liver Yang rising, most often applied for dizziness, tinnitus, and spontaneous sweating. Modern research has identified Calcium among its active constituents.

Part used: Shell

Also Known As

Ostrea gigas Ostrea

Latin: Concha Ostreae | Pinyin: Mu Li | Chinese: 牡蛎

TCM Properties

Taste
salty, astringent
Temperature
slightly cold
Channels
Liver, Kidney

Traditional Use

Primary Actions

  • Pacifies the Liver and subdues Yang; treats dizziness, tinnitus, headache, and irritability from Liver Yang rising
  • Softens hardness and dissipates nodulation; used for scrofula, goiter, and abdominal masses
  • Astringes and stops discharge; treats spontaneous sweating, night sweats, spermatorrhea, and abnormal uterine bleeding from unstable Essence

Secondary Actions

  • Calcined (Duan) form used specifically for its astringent action; raw (Sheng) form preferred for Liver Yang subduing and nodule-softening

Classic Formulas

  • Gui Zhi Jia Long Gu Mu Li Tang (Cinnamon Twig Decoction Plus Dragon Bone and Oyster Shell)

Classical References

  • Shang Han Lun (Treatise on Cold Damage, Zhang Zhongjing, c. 200 CE) pairs Mu Li with Long Gu (Dragon Bone) for anchoring floating Yang and calming the Spirit

Modern Research

Active Compounds

  • Calcium carbonate
  • Trace minerals (zinc, magnesium)
  • Conchiolin protein

Studied Effects

  • Calcium carbonate content supports traditional acid-neutralizing use for peptic complaints
  • Shell-derived compounds studied for bone-supportive and mineral-supplementation potential, similar to related mollusk shell materials (Zhen Zhu Mu)

Safety & Interactions

Cautions

  • Must be smashed and decocted first due to its mineral density
  • Spleen-Stomach Deficiency Cold

Conditions

Frequently Asked Questions

What is Oyster Shell used for?

Oyster Shell is traditionally used to Pacifies the Liver and subdues Yang; treats dizziness, tinnitus, headache, and irritability from Liver Yang rising, Softens hardness and dissipates nodulation; used for scrofula, goiter, and abdominal masses, Astringes and stops discharge; treats spontaneous sweating, night sweats, spermatorrhea, and abnormal uterine bleeding from unstable Essence. Research has investigated its effects on: Calcium carbonate content supports traditional acid-neutralizing use for peptic complaints; Shell-derived compounds studied for bone-supportive and mineral-supplementation potential, similar to related mollusk shell materials (Zhen Zhu Mu).

What are other names for Oyster Shell?

Oyster Shell is also known as Ostrea gigas, Ostrea. In TCM: 牡蛎 (Mu Li); Concha Ostreae.

Is Oyster Shell safe during pregnancy?

Oyster Shell is generally considered safe during pregnancy in normal amounts. Therapeutic or concentrated doses should be discussed with a qualified practitioner before use.