Fruits and seedsPhlegm-resolvingArmeniacae Semen Amarum

Ku Xing Ren (Ansu Apricot Seed)

苦杏仁 · Ku Xing Ren

Phlegm-resolving herb in Traditional Chinese Medicine. Traditional functions: Directs lung qi downward, stops cough and wheezing, and moistens the intestines.

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Quick Facts

Latin Name	Armeniacae Semen Amarum
Chinese Name & Pinyin	苦杏仁 · Ku Xing Ren
Medicinal Part	Fruits and seeds
Efficacy Category	Phlegm-resolving
Botanical Origin	The dried mature seed of Prunus armeniaca L. var. ansu Masim., Prunus sibirica L., Prunus mandshurica (Maxim.) Koehne or Prunus armeniaca L.(Rosaceae).
Nature & Flavour	Bitter; Slightly warm; Slightly toxic
Channels Entered	Lung, Large Intestine

What Is Ku Xing Ren?

Ku Xing Ren (Ansu Apricot Seed) is a medicinal herb of Traditional Chinese Medicine.

Primarily produced in the Chinese provinces of Liaoning, Inner Mongolia, Hebei, Shandong.

Nature & Flavour: Bitter; Slightly warm; Slightly toxic
Channels Entered: Lung, Large Intestine

Ku Xing Ren: Materia Medica Profile

Identification & Quality Standard

Armeniacae Semen Amarum

Botanical Origin

The dried mature seed of Prunus armeniaca L. var. ansu Masim., Prunus sibirica L., Prunus mandshurica (Maxim.) Koehne or Prunus armeniaca L.(Rosaceae).

Production Regions

Primarily produced in the Chinese provinces of Liaoning, Inner Mongolia, Hebei, Shandong.

Quality Requirements

Superior ku xing ren consists of consistent kernels, full, intact, with bitter taste. Tian xing ren has consistent large kernels, full, fat, without oil diffusion.

Macroscopic Features

Ku xing ren: Flat heart shape, 1~1.9cm long, 0.8~1.5cm wide, 0.5~0.8cm thick. Externally yellowish-brown to dark brown, one end is pointed; another end is blunt round, fat, asymmetrical right and left sides. Pointed end has short linear hilum on one side, chalaza on the round end has numerous dark brown veins. Seed coat is thin, 2 cotyledons, milky-white, oily. faint odor; bitter taste. Tian xing ren: dried seed, flat heart shaped, 1.6~2.1cm long, 1.2~1.6cm wide, pointed apex, round base, symmetrical sides, obvious hilum, seed coat is thicker than that of bitter xing ren; pale yellowish-brown, numerous veins came out from chalaza forming longitudinal indented lines. Fractured surface is white. Cotyledon side often has gap. faint odor; slightly sweet taste.

Traditional TCM Properties

Bitter; Slightly warm; Slightly toxicLungLarge Intestine

Traditional Functions

Directs lung qi downward, stops cough and wheezing, and moistens the intestines. Apply to cough and labored breathing, and constipation from intestinal dryness.

How Ku Xing Ren Is Used in TCM

In the Chinese materia medica, Ku Xing Ren is classified among the Phlegm-resolving herbs.

Frequently Asked Questions

What is Ku Xing Ren? Are sweet apricot seed and peach kernel the same?

Official Ku Xing Ren (苦杏仁) is the dried ripe seed of Prunus armeniaca var. ansu and related species. The pharmacopoeial name is Armeniacae Semen Amarum; it is slightly toxic. Sweet apricot seed is sweet-neutral: moistens the Lung and stops cough, with lower toxicity. Peach kernel is bitter-sweet and neutral: moves Blood, dispels stasis, moistens the intestines and frees the stool. The three cannot be interchanged by equal weight. Write Ku Xing Ren. Yin-vacuity cough and asthma and loose stool are contraindicated.

What are the TCM properties and traditional uses of Ku Xing Ren?

According to the Chinese Pharmacopoeia, Ku Xing Ren is bitter and slightly warm, slightly toxic, enters the Lung and Large Intestine channels, and acts to descend qi, stop cough and calm panting, moisten the intestines and free the stool. It is used for cough and asthma, chest fullness with much phlegm, and intestinal dryness with constipation. Bitter, slightly warm and slightly toxic, it suits Lung qi counterflow—not yin-vacuity cough and asthma, or loose stool.

How do you choose raw versus stir-fried seed? Can sweet apricot seed replace it?

Raw seed is stronger for descending qi. Stir-frying leans to moistening the intestines. Sweet apricot seed leans to moistening the Lung; it cannot replace descending qi by equal weight. Commercial bitter-apricot-seed tea is not equal-weight pieces.

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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.