Os Draconis Praeparata
Aliases：Duan Bai Long Gu, Duan Tu Long Gu, Duan Gu Hua Shi, Duan Long Gu Tou, Duan Qing Hua Long Gu, Duan Fen Long Gu
Calcined Dragon Bone (Duàn Lóng Gǔ) is a processed product of the Chinese medicinal Long Gu (Dragon Bone). It is made from the fossilized bones of ancient mammals such as hipparions (three‑toed horses), rhinoceroses, deer, cattle, elephants, or the fossilized tusks (incisors) of elephants. After cleaning and selection, it is processed by direct calcination (firing over direct heat).
Efficacy & Actions
Calm the spirit and relieve convulsions (calm fright and stabilize the mind), arrest sweating and astringe essence, stop bleeding and astringe the intestines, promote tissue regeneration and close sores.
Indications
Palpitations and insomnia, epilepsy and manic disorders, spontaneous sweating and night sweats, spermatorrhea and enuresis, flooding and spotting (metrorrhagia) and leukorrhea, chronic diarrhea and dysentery, non‑healing ulcers, and traumatic bleeding.
Modern Pharmacology
Sedative and anticonvulsant: The calcium ions it contains inhibit neuromuscular excitability and have a central depressant effect. Astringent and hemostatic: After calcination, it has strong water absorption and significant astringent properties, shortening clotting time. Anti‑ulcer and wound healing: Promotes ulcer healing and reduces exudation. Regulation of calcium‑phosphorus metabolism: Supplies calcium, but absorption is limited.
Ingredients
Inorganic salts: Calcium carbonate (CaCO₃), calcium phosphate [Ca₃(PO₄)₂]. Trace elements: Iron, potassium, sodium, magnesium, zinc, manganese, etc. Others: Part of the calcium carbonate decomposes into calcium oxide after calcination, making the texture brittle.
Usage & Dosage
Internal use: 9–15 g in decoction, should be decocted first; or used in pills or powders. External use: Appropriate amount, ground into powder for dusting or applied as a paste.
Contraindications
Contraindicated populations: Avoid in cases of damp‑heat accumulation or internal excess fire. Use with caution during pregnancy. Precautions for use: Duan Longgu has strong astringent properties. It should not be used in the early stages of exterior syndrome or in cases of excess heat patterns. Adverse reactions: Safe at conventional doses. Overdose may cause constipation.
Selected Formulas
1. Duan Longgu (Calcined Dragon Bone) combined with Muli (Oyster Shell) Both herbs can astringe Yin and subdue hyperactive Yang, calm the spirit and relieve convulsions, and astringe and secure. Duan Longgu is better at calming the spirit, relieving convulsions, and astringing to stop collapse. Muli is better at benefiting Yin, reducing heat, transforming phlegm, and softening hardness. When used together, they harmonize Yin and Yang, enhancing the effects of calming the spirit, astringing Yin, subduing Yang, securing and astringing, stopping bleeding, and stopping leukorrhea. Indications: Irritability, palpitations, dizziness, tinnitus, forgetfulness, insomnia due to Yin deficiency with Yang hyperactivity. Cough, wheezing, profuse sweating with collapse due to disharmony between Heart and Kidney, or deficiency of Lung and Kidney. Chronic diarrhea, chronic dysentery, spermatorrhea, turbid urine, flooding and spotting (metrorrhagia), leukorrhea. 2. Duan Longgu combined with Shayuanzi (Astragalus complanatus seed) and Qianshi (Euryale seed) Duan Longgu astringes and secures. Shayuanzi and Qianshi tonify the Kidney and astringe essence. When used together, they both supplement the insufficiency of Kidney essence and astringe the leakage of essence. Indications: Spermatorrhea, seminal emission due to Kidney deficiency.
Daily Consumption
Dragon Bone Congee Ingredients: 30 g calcined dragon bone (Duan Longgu), 100 g glutinous rice, an appropriate amount of brown sugar. Preparation: Crush the calcined dragon bone, add 200 ml of water, decoct for 1 hour, then strain to remove the residue and retain the liquid. Add the glutinous rice and 600 ml of water, cook into a thin congee. Finally, stir in the brown sugar to taste. Actions: Calms the spirit, subdues hyperactive yang, astringes and secures. Indications: Spermatorrhea, as well as postpartum excessive sweating, night sweats, spontaneous sweating, flooding and spotting (metrorrhagia), etc.
Medicinal Parts
processed fossil bone
Selection & Storage
Store in a dry place, protected from moisture.