A practical guide to Long Chi: what it is, how Traditional Chinese Medicine uses it, the classical formulas it appears in, and who should be careful with it.
Last reviewed Oct 28, 2026| Latin Name | Dentis Draconis |
|---|---|
| Chinese Name & Pinyin | 龍齒 · Long Chi |
| Medicinal Part | Minerals |
| The item | Long Chi is the tooth fossil of ancient mammals. Long Gu (dragon bone, fossilized bone) is not this drug. |
| Nature and channels | Neutral, astringent, sweet. Enters the Heart and Liver. Neutral astringent-sweet settles fright, quiets the spirit, clears heat, and relieves vexation. |
| Pharmacopoeia line | Settles fright and quiets the spirit; clears heat and relieves vexation. Used for fright palpitations, restless sleep, and irritability of an unsettled spirit. |
| Pattern cues | Restless sleep. Easy startling. Fidgeting. Irritability. Night heat. Dry mouth. |
| In this article | Long Chi versus Long Gu. Settling the spirit versus securing the body's leaks. Why it is boiled first. Why a cold weak spleen-stomach should skip it. Who needs a clinic. |
Long Chi (龙齿; Lóng Chǐ; Latin: Dens Draconis; English: dragon tooth fossil) is a fossil — the teeth of ancient mammals such as elephants, rhinos, and three-toed horses — worn smooth like a hard ceramic shard from a riverbed, with a long history in Chinese medicine for unsettled minds and restless sleep. It is neutral, astringent, and sweet, enters the Heart and Liver channels, and its core actions are to settle fright and quiet the spirit, and to clear heat and relieve vexation. It is the herb for a mind that will not settle. The usual amount is 10–15 g in a decoction, boiled first. It is not boiled with the rest, and it is never taken raw as a powder on its own.
It is not Long Gu. Dragon bone is also neutral, sweet, and astringent — but its astringing is stronger, and it also secures the body's leaks, from sweat to loose stools. It is not a "sleeping pill" herb either — the classic fit is an unsettled spirit with some heat, not every insomnia. In pure qi-blood deficiency — long-term weakness, a sallow face, no heat at all — or in a cold weak spleen-stomach, using it on your own is a poor match. Palpitations that keep worsening, or insomnia that will not settle, need a clinic first. Do not take it yourself for a long time.
It is used most often for three patterns:
Neutral, astringent, and sweet, it is not a daily "calm herb" to keep adding. Holding and settling when there is no agitation, or when weakness is the root, blocks the qi instead of helping.
When the heart spirit is unsettled — from worry, heat, or fright — sleep turns restless, the mind jumps at sounds, and a low-grade heat sits in the chest. Long Chi is neutral, astringent, and sweet. It sinks, settles, and holds, which is why it appears in An Shen Ding Zhi Wan (Spirit-Settling Pill)–type formulas. It holds more than it scatters. In pure qi-blood deficiency, or with no agitation at all, more makes it worse.
Long Chi is not a catch-all calm or sleep herb. In pure qi-blood deficiency, in a cold weak spleen-stomach, or in pregnancy, using it alone is a poor match. Whether it belongs in a formula, and at what dose, should be decided by a licensed Chinese medicine practitioner after pattern diagnosis.
Identification & Quality Standard
Dentis Draconis
Botanical Origin
The fossilized tooth of ancient mammals such as Stegodon, Mastodon or Elephant (Elephantidae).
Production Regions
Primarily produced in Shanxi, Henan, Hebei, Inner Mongolia.
Quality Requirements
Superior is complete, heavy, clean, without sand.
Irregular tooth-like pieces, 5~15cm. Externally grayish-white or dark brown, often with tooth root. Hard, heavy. Faint odor, tasteless.
Classic texts and trade experience favor fossil beds in the north and northwest of the country, but quality still depends on variety, harvest time, processing, and storage. Good Long Chi is irregular and blocky, with deep longitudinal striations or cracks, hard, with a rough, porcelain-glossed break; a faint slightly fishy smell, no obvious off-odor. Raw pieces are dark brown to gray-yellow; calcined pieces are gray-white to blue-gray and more brittle. The common look-alikes are modern animal tooth fossils or other fossil bones — with messy surface texture, no tooth striations, and no porcelain gloss on the break — best told apart by a specialist.
Sweet, Astringent; CoolHeartLiver
Some early doctors stressed the settling-astringent side — for fright epilepsy and mania; others later emphasized the clearing quality — for vexing heat and mild irritability; still others drew the line — it fits excess or mixed patterns, not pure deficiency in large amounts; and some flagged the caution — a weak spleen-stomach with poor digestion should not take it long, lest the astringing hamper the spleen's transport.
Traditional Functions
Settles fright and quiets the spirit, clears heat and removes vexation.
(1) Traditional action: settling and holding a scattered, unsettled spirit. (2) Typical patterns: restless sleep, easy startling, a fidgeting mind, sitting still barely possible. (3) Usual pairings: Suan Zao Ren (sour jujube seed) and Bai Zi Ren (arborvitae seed) to nourish the heart and quiet the spirit; with vexing heat, Zhi Zi (gardenia) and Dan Zhu Ye (bamboo leaf) to clear it. (4) Not for self-use: pure qi-blood deficiency with an unsettled spirit — the astringing can block qi and blood circulation; consult a practitioner first.
(1) Traditional action: clearing the low-grade heat that rides on an unsettled spirit. (2) Typical patterns: irritability, dry mouth with a bitter taste, night heat, a red tongue with a thin yellow coat. (3) Usual pairings: Zhi Mu (anemarrhena) and Mai Dong (ophiopogon root) to clear heat and nourish the fluids; with scanty dark urine, Hua Shi (talc) and Tong Cao (ricepaper pith) to clear heat and move water. (4) Not for self-use: a cold weak spleen-stomach with frequent loose stools — the cold-clearing can deepen the chill.
Long Chi pairs classically with Suan Zao Ren: the fossil sinks, gathers, and settles the scattered spirit; the sour jujube seed nourishes the heart blood and quiets the spirit — one settles the surface agitation, the other rebuilds the root supply. The pair fits restless sleep and irritability of heart-blood deficiency with an unsettled spirit. This pair belongs to a practitioner's pattern diagnosis — pure excess or qi-blood deficiency calls for a different team.
Modern research offers useful context, but Traditional Chinese Medicine prescribes on whole-pattern diagnosis rather than isolated compounds.
Modern testing of this fossil finds hydroxyapatite as the main component, plus small amounts of calcium, phosphorus, iron, and magnesium trace elements — inorganic fossil material, not plant compounds. In vitro, no direct inhibition of bacteria or viruses has been observed so far. In animal experiments, some studies observe that extracts may slow spontaneous activity in mice — a hint of potential sedation. No clear human clinical conclusion has been reached yet.
Current work centers on a possible settling-calming effect: the hydroxyapatite and trace elements may modulate the nervous system to some degree; experiments observe that extracts may lengthen sleep time in mice — animal data only, not human efficacy. The mechanism, the active constituents, and the targets are not yet clear. Human research is still needed.
Nature and flavor: Long Chi is neutral, astringent and sweet; Long Gu is also neutral, sweet and astringent with a light salty note — its astringing is a little stronger. Focus: Long Chi leans to clearing the vexing heat of an unsettled spirit while settling it; Long Gu leans to astringing and securing — beyond calming, it also checks the body's leaks, from spontaneous sweating to seminal loss. Tendency: Long Chi's sinking targets the heart spirit's floating and scattering, without touching other organ qi; Long Gu's sinking is stronger — it not only calms but also holds the intestines, sweat, and the lower gates, with a wider astringing reach. Best fit: Long Chi for unsettled spirit with mild heat — irritability, dry mouth, night heat; Long Gu for unsettled spirit with leaks — heavy sweating, seminal loss, diarrhea that will not stop. Who should avoid: Long Chi is wrong for pure qi-blood deficiency and for long use in a cold weak spleen-stomach; Long Gu shares those cautions and is also wrong for internal damp-heat — its astringing can trap the damp. Where you meet them: Long Chi in calming formulas that also clear heat; Long Gu in formulas for leak-securing — spontaneous sweating, night sweats, seminal loss — less often as an everyday mild calmer.
In short, Long Chi settles the spirit and clears vexing heat; Long Gu secures the body's leaks and calms as part of that. Both fit unsettled-spirit patterns — but they are not stand-ins for each other.
A formula is a coordinated team; a single herb cannot copy a full formula's effect. Long Chi is a supporting player — alone it cannot match the formula's balanced work. The doses and pairings are designed as a whole, and adjusting any one herb can shift the whole effect. Do not self-formulate from web articles — a herb that works in a formula does not automatically work the same way alone, and an ill-set dose can bring discomfort.
Example 1 — Long Chi sour jujube tea: sheng Long Chi 5 g (crushed), Suan Zao Ren 3 g — steeped in a teapot with boiling water, covered 10 minutes; may be re-steeped 2–3 times. Fit: mild unsettled spirit, waking easily at night, with slight irritability — short-term care for stressed office workers or the elderly. Not for: a cold weak spleen-stomach, frequent diarrhea, or pregnancy. Frequency: 2–3 times a week, no more than 1 week straight. Example 2 — Long Chi lotus porridge: duan Long Chi 10 g (boiled first 30 minutes, use the liquid), lotus seeds 15 g, rice 50 g — cooked into a thin porridge; a little rock sugar optional. Fit: unsettled spirit with mild heat, restless sleep, and a slightly weak digestion. Not for: damp-heat with a clearly bitter mouth. Frequency: once every 2 weeks, no frequent use. Long Chi is a medicinal piece, not ordinary food — never raise the dose or make it a daily drink; check with a professional first.
Sheng Long Chi clears vexing heat and settles — for mild unsettled spirit with heat; it is boiled first because the hard fossil releases its material slowly — boil first 30 minutes. Duan Long Chi settles and holds more — for patterns that need stronger astringing; it is more brittle and also boiled first 20 minutes. At home, soak the pieces 30 minutes, boil hard, then simmer; first-boiled pieces go in separately before the other ingredients. Raw and calcined forms differ — do not swap them casually.
The classic range is 10–15 g as a medicinal dose; food-use amounts are 5–10 g — smaller than medicinal doses. Food amounts suit only short-term mild care and never replace medicinal care. Not for long continuous use — a short course of 1–2 weeks; if nothing settles, consult a practitioner. Pregnant women, children, the elderly, and people with liver or kidney concerns ask a practitioner or pharmacist first.
Pure qi-blood deficiency with an unsettled spirit — palpitations, fatigue, a sallow face, no heat at all; a cold weak spleen-stomach — frequent belly pain, loose stools; pregnancy and nursing — no use without professional review; children and the elderly — weaker metabolism, guidance only; liver or kidney impairment — tell the practitioner first; allergy to fossil-type materials — avoid; people on sedatives or antidepressants — consult a doctor before use, to avoid interactions.
Long Chi may add to the effect of sedative medicines — anyone on them should ask a doctor to adjust the dose; it may also affect the absorption or metabolism of anticoagulants, blood-pressure, and blood-sugar medicines — ask a doctor or pharmacist first. No blanket "food clash" with ordinary foods is established, but herbs can interact with specific medicines. While using it, go easy on overly spicy, greasy, and raw-cold foods.
Misuse can bring stomach discomfort — poor appetite, bloating, diarrhea; too much or too long can worsen irritability and dry the mouth. Stop and seek care at once for marked discomfort, an allergic reaction (rash, itching, trouble breathing), persistent vomiting, confusion, or a rapid worsening of symptoms.
Nong's Long Chi (Dragon Teeth) Single Herb 5:1 Concentrated Granules
$44.74
Hoi Tin Long Chi (Dragon Tooth) Single Herb 20:1 Concentrated Granules
$21.92
Hoi Tin Zhen Gan Xi Feng Tang (Sedate the Liver and Extinguish Wind Decoction) 5:1 Concentrated Granules
$36.06
Han's Zhen Gan Xi Feng Tang (Settling the Liver & Extinguishing Wind Decoction) 5:1 Concentrated Granules
$55.99
Hoi Tin An Shen Ding Zhi Wan (Calm the Spirit and Settle the Will Formula) 5:1 Concentrated Granules
$37.45
Medical Disclaimer — This article is provided for educational purposes only and describes traditional Chinese medicine concepts. It is not medical advice, and it is not intended to diagnose, treat, cure or prevent any disease. Always consult a qualified practitioner before using any herb, particularly if you are pregnant, nursing, taking medication or managing a diagnosed condition.
