Long Chi (龙齿) — TCM Dragon Teeth for Fright, Panic, Shen-Calming & Liver-Yang

At a Glance

Herb: Long Chi
Chinese name: 龙齿 (Lóng Chǐ)
Latin name: Mastodi Dentis Fossilia
Nature: Cool
Taste: Astringent / Sweet
Meridian: Heart / Liver
Category: Herbs that Calm the Spirit
Introduction: Long Chi (龙齿, Dragon Teeth) is the fossilized dental material of the same ancient megafauna that yields Long Gu (Dragon Bone) — prehistoric elephants, rhinoceroses, and large mammals of the Pleistocene epoch, excavated from the same sedimentary deposits in northern China. Documented in the Shennong Bencao Jing alongside Long Gu, Long Chi is considered the superior Shen-calming of the two — while Long Gu anchors Yang and astringes broadly, Long Chi is more specifically targeted at the Heart Shen, calming fright, anxiety, and disturbed sleep with a stronger settling action on the emotional and mental sphere. The dense calcium phosphate matrix of fossilized enamel and dentine, along with trace minerals, modulates neuronal excitability through calcium-dependent mechanisms; enamel’s higher mineral density compared to cortical bone is thought to account for Long Chi’s stronger Shen-settling action relative to Long Gu. In modern clinical practice Long Chi and Long Gu are often used interchangeably or in combination, with Long Chi preferred when fright, panic attacks, or severe emotional instability is the primary presentation.

Calms the Shen and settles fright — severe anxiety, panic attacks, fright palpitations, insomnia
Anchors Liver Yang — dizziness, headache from Yang rising
Clears Heat from the Heart — irritability, restlessness, mouth sores from Heart Fire
Astringes (milder than Long Gu) — sweating, spermatorrhea when combined with Long Gu

Severe anxiety and fright-type insomnia: preferred over Long Gu for emotional disturbance and panic
Palpitations from Heart-Qi deficiency with fright: combined with Ren Shen, Fu Shen, Yuan Zhi
Epilepsy and febrile convulsions: combined with Ci Shi, Gou Teng, Dan Nan Xing
Liver-Yang rising with headache and dizziness: combined with Long Gu, Mu Li
Childhood night fright and night crying: combined with Chan Tui, Gou Teng

Dosage: 15–30 g in decoction; pre-decoct 30–60 minutes
Calcined form (煅龙齿) is more astringent; raw form stronger for Shen-calming
Pre-decoct mandatory to release mineral constituents
Use with caution in Damp-Heat — astringent mineral may trap pathogen
Distinguished from Long Gu: Long Chi is stronger for Shen-calming and fright; Long Gu is stronger for anchoring Yang and astringency — clinical use overlaps considerably
Sourcing from the same fossil deposits as Long Gu; non-renewable; quality varies widely

An Shen Ding Zhi Wan (安神定志丸) — Long Chi + Fu Shen + Yuan Zhi + Ren Shen + Shi Chang Pu; Heart-Qi deficiency fright and anxiety
Chai Hu Jia Long Gu Mu Li Tang — Long Chi sometimes substituted for Long Gu in modern practice
Combined with Long Gu and Mu Li as a trio for comprehensive Yang-anchoring and Shen-calming
Combined with Suan Zao Ren and Bai Zi Ren for Blood-deficiency insomnia with fright component

Dragon Teeth (龙齿) + Polygala Root (远志) + Poria with Pine Root (茯神) + Ginseng (人参) + Acorus Root (石菖蒲) → An Shen Ding Zhi Wan (安神定志丸) — settle fright, calm spirit, treat anxiety and palpitations
Dragon Teeth (龙齿) + Mother of Pearl (珍珠母) + Sour Jujube Seed (酸枣仁) → anchor spirit, nourish blood, treat fright insomnia with heat signs
Dragon Teeth (龙齿) + Gambir Vine (钩藤) + Gastrodia Root (天麻) → clear heat, stop wind, calm fright convulsions in children
Dragon Teeth (龙齿) + Oyster Shell (牡蛎) + Dragon Bone (龙骨) → triple heavy-settling formula for severe floating yang and agitation
Dragon Teeth (龙齿) + Rehmannia Root (生地) + Coptis Rhizome (黄连) → clear heart heat, settle spirit for insomnia with heat signs; distinction from Dragon Bone (龙骨): Dragon Teeth (龙齿) (fossilized teeth) is cooler and stronger at settling fright; Dragon Bone (龙骨) (bones) is warmer and stronger at astringing; Dragon Teeth (龙齿) preferred when there is a heat component to spirit disturbance — fright, fear, childhood convulsions, liver-heat insomnia; preparation: decoct 30 min before other herbs; calcined Dragon Teeth (煅龙齿) stronger astringent; raw Dragon Teeth (生龙齿) stronger spirit-settling

Sedative / fright-settling
- calcium ions + hydroxyapatite mineral mass — reduce neuronal excitability
- calcium modulates voltage-gated channels
- heavy density provides physical ‘settling’ effect
- zinc — inhibitory neuromodulator via glycine and GABA-B receptors
- slightly stronger anticonvulsant than 龙骨 due to higher zinc content
- clinical use for childhood febrile convulsions and adult anxiety with heat signs
Anticonvulsant
- zinc + calcium — raise seizure threshold
- stabilize neuronal membranes
- reduce NMDA receptor overactivation
Antipyretic
- cool nature — mild temperature-reducing action in febrile convulsions
- zinc inhibits prostaglandin synthesis
Astringent
- calcium salts precipitate proteins — mild astringent for sweating
- weaker than 龙骨
Antacid
- calcium carbonate — neutralizes gastric acid
- less used for this than 龙骨/牡蛎 due to higher cost
Bone/dental mineral supply
- hydroxyapatite — bioavailable calcium and phosphate
- supports bone metabolism

Shen Nong Ben Cao Jing: ‘Governs fright epilepsy in children and adults, mania-withdrawal disorder, frantic running, bound qi below the heart with inability to breathe, and all types of convulsive spasm.’
Ming Yi Bie Lu: ‘Children’s fright epilepsy with fever so intense others cannot touch the body; cold and heat between the bones in adults; kills parasitic toxins.’
Ben Cao Gang Mu: ‘Dragon Teeth treats adults’ fright epilepsy and manic heat, and children’s five frights and twelve types of epilepsy; its function is similar to Dragon Bone, but its cooler nature makes it superior in settling fright.’
Ben Cao Jing Shu: ‘Dragon Teeth — the Ben Jing governs adults’ and children’s fright epilepsy, frantic running, bound qi below the heart with inability to breathe, and convulsive spasm… Its governance of adults’ fright epilepsy, frantic running, and children’s fright epilepsy is due to its ability to cool heart-liver heat and heavily settle and descend counterflow.’