This product is the shell of the long oyster (Ostrea gigas Thunb.), Dalian Bay oyster (O. talienwhanensis Crosse), or river oyster (O. rivularis Gould) from the oyster shell family. It is distributed along the coastal areas of the mainland. It can be harvested all year round, with the highest yield in winter and spring. After harvesting, the flesh is removed, and the shell is washed and dried. It is used raw or calcined. It is crushed before use.

bubble_chart Properties and Meridians

Salty and astrigent, slightly cold. act on liver and kidney channels.

bubble_chart Efficacy

Pacifying liver and subduing yang, softening hardness and dissipating mass, astringing and consolidating.

bubble_chart Indications

1. Used for ascendant hyperactivity of liver yang, dizziness, and dizzy vision. This product is salty, cold, and heavy in nature, with effects similar to Abalone Shell in pacifying liver and subduing yang. It is often used to treat conditions such as water failing to nourish wood, yin deficiency with yang hyperactivity, vertigo, and tinnitus. It is commonly combined with Fossil Bone, Tortoise Carapace, Achyranthes Root, etc., as in 鎮肝息風湯. It is also used to treat prolonged febrile diseases that scorch true yin, leading to internal stirring of deficient wind and convulsions of the limbs. It is often combined with Tortoise Carapace, turtle carapace, Unprocessed Rehmannia Root, etc., as in Major Wind-Stabilizing Pearl.
2. Used for subcutaneous nodules, scrofula, abdominal masses, etc. Oyster shell is salty in taste and has the effect of softening hardness and dissipating masses. It is used to treat subcutaneous nodules and scrofula caused by phlegm-fire stagnation, often combined with Thunberg Fritillary Bulb, Scrophularia Root, etc., as in Scrofula-Eliminating Pill. It is also used to treat abdominal masses caused by blood stasis and qi stagnation, often combined with turtle carapace, Salvia, Zedoary Rhizome, etc. In modern times, it is commonly used to treat liver and spleen enlargement with good efficacy.
3. Used for various syndromes of slippage and desertion. This product has an astringent taste and, when calcined, has a similar astringent and consolidating effect as calcined Fossil Bone. It is often used in mutual reinforcement with calcined Fossil Bone to treat seminal emission, spermatorrhea, enuresis, frequent urination, menorrhagia and metrostaxis, leukorrhea, spontaneous sweating, night sweat, and other syndromes of deficiency and slippage. It is combined with corresponding tonifying deficiency and astringent medicinals. In recent years, there have been reports of using decocted oyster shell to treat pulmonary subcutaneous nodules and night sweat with good efficacy.
4. In addition, calcined oyster shell has an astringent and acid-suppressing effect, and can be used to treat stomachache and acid regurgitation. It is often combined with cuttlebone sepium and Thunberg Fritillary Bulb as a fine powder for internal use to achieve efficacy.

bubble_chart Documentation

1. Benjing: "Mainly treats fright, anger, and qi, relieves spasms and laxity, scrofula, and leukorrhea with red and white discharge in women."
2. Bielu: "Regulates the vacuity and heat of the defensive and nutritive qi, which come and go irregularly, relieves fullness and stops sweating, heart pain, qi stagnation, quenches thirst, eliminates old blood, astringes the large and small intestines, stops urination and defecation, treats seminal emission, pharyngitis, cough, and heat and stuffiness below the heart and ribs."
3. Bencao Beiyao: "Salty to soften hardness and resolve phlegm, dissipates scrofula and subcutaneous nodes, old blood, hernia, and masses. Astringent to stop leakage, treats seminal emission, flooding and vaginal discharge, stops cough and restrains sweating, secures the large and small intestines."

bubble_chart Usage and Dosage

Decoct 10-30g, crush before use. Except for astringent and solidifying purposes which require calcination, use raw for all other purposes.

bubble_chart Modern Pharmacology

This product contains 80-95% calcium carbonate, calcium phosphate, and calcium sulfate, along with magnesium, aluminum, silicon, iron oxide, and organic matter. Upon calcination, the carbonates decompose to produce calcium oxide, and the organic matter is destroyed. The calcium salts present have antacid and Grade I sedative and anti-inflammatory effects. It has certain therapeutic effects on gastric and duodenal ulcers and can also enhance immunity.