Rou Dou Kou (肉豆蔻) — Nutmeg | TCM Herb Guide

At a Glance

Herb: Rou Dou Kou
Chinese name: 肉豆蔻 (Ròu Dòu Kòu)
Latin name: Myristica fragrans seed kernel
Nature: Warm
Taste: Acrid
Meridian: Spleen / Stomach / Large Intestine
Category: Herbs that Stabilize and Bind
Introduction: Rou Dou Kou (肉豆蔻), Semen Myristicae, is the dried seed kernel of Myristica fragrans, the tropical nutmeg tree native to the Maluku Islands. In TCM it warms the spleen and stomach, moves qi, and astringes the intestines to stop chronic diarrhea from cold deficiency. Its aromatic volatile oils — chiefly myristicin and elemicin — account for its warming, carminative, and antidiarrheal properties. It must be processed (roasted or baked) to reduce its mild toxicity before internal use.

Spleen-kidney yang deficiency with chronic diarrhea: dawn diarrhea (cock-crow diarrhea), loose stools — combines with Bu Gu Zhi, Wu Zhu Yu, Wu Wei Zi
Cold-type abdominal pain and distension from qi stagnation — combines with Mu Xiang, Gan Jiang
Vomiting and hiccup from stomach cold — combines with Ding Xiang, Ban Xia
Chronic dysentery from deficiency cold — combines with Dang Shen, Bai Zhu

Dosage: 3–9 g in decoction; must use processed (roasted/baked) form — raw is mildly toxic
Contraindicated in diarrhea from damp-heat or food stagnation
Contraindicated in heat patterns — warm aromatic nature may exacerbate heat
Large doses (>15 g) may cause hallucinations due to myristicin — observe dose limits
Avoid in pregnancy

Si Shen Wan (四神丸): Rou Dou Kou, Bu Gu Zhi, Wu Zhu Yu, Wu Wei Zi — warms spleen and kidney, stops dawn diarrhea; classic formula for cock-crow diarrhea
Rou Dou Kou Wan (肉豆蔻丸): Rou Dou Kou, Mu Xiang, Gan Jiang, Bai Zhu — warms middle, moves qi, stops cold diarrhea
Zhen Ren Yang Zang Tang (真人养脏汤): Rou Dou Kou, Ren Shen, Bai Zhu, Ying Su Ke, He Zi, Dang Gui — astringes intestines, stops chronic dysentery

补骨脂 (Bǔ Gǔ Zhī) + 吴茱萸 (Wú Zhū Yú) + 五味子 (Wǔ Wèi Zǐ) — four-miracle pill (四神丸): spleen-kidney yang deficiency with cock-crow diarrhea (五更泄泻). 2. 党参 (Dǎng Shēn) + 白术 (Bái Zhú) + 干姜 (Gān Jiāng) — spleen cold with chronic diarrhea and poor appetite. 3. 木香 (Mù Xiāng) + 砂仁 (Shā Rén) — cold-damp spleen causing abdominal distension and diarrhea. 4. 诃子 (Hē Zǐ) — chronic diarrhea and dysentery from deficiency. 5. 炮姜 (Páo Jiāng) + 人参 (Rén Shēn) — spleen yang collapse with undigested food in stool. Source: 证治准绳 (四神丸), 本草纲目.

Antidiarrheal: trimyristin inhibits intestinal smooth muscle contractility; reduces secretory diarrhea by blocking camp-dependent cl⁻ channels. carminative: volatile oils inhibit intestinal gas formation and reduce flatulence. anti-inflammatory: mdga inhibits cox-2, nf-κb, and reduces pge₂. antidepressant: myristicin inhibits mao-a; potentiates serotonin — may contribute to formula efficacy in emotionally triggered digestive disorders. hepatoprotective: nectandrin b reduces ccl₄ hepatotoxicity via nrf2 activation. caution: myristicin toxic in overdose
- >5 g nutmeg
Causes hallucinations, liver damage; therapeutic dose 3–9 g of processed
- 煨) form is safe.

Kai Bao Ben Cao (《开宝本草》): ‘Governs warming the center, digesting food and stopping diarrhea; treats accumulated cold Heart and abdominal distension and pain, sudden turmoil and malevolence, ghost-qi cold stagnation, vomiting of foamy cold qi, and infantile nursing sudden turmoil.’
Ben Cao Gang Mu (《本草纲目》): ‘Nutmeg warms the Spleen and Stomach, secures the Large Intestine; treats deficiency diarrhea and cold dysentery — because it can secure fatty substances and astringes the Large Intestine.’
Ben Cao Bei Yao (《本草备要》): ‘Acrid and warm; warms the Spleen and Stomach, astringes the Large Intestine, stops diarrhea and dysentery; treats stomach cold with vomiting and counterflow, epigastric and abdominal deficiency pain, and digests food and disperses distension.’