Herb Resin / Sap (树脂 shù zhī / 汁 zhī)

Song Xiang

Pine Resin · 松香

Pinus massoniana Lamb. and other Pinus species · Colophonium

Also known as: Song Zhi (松脂), Huang Xiang (黄香), Bai Song Xiang (白松香)

Images shown are for educational purposes only

Song Xiang (Pine Resin) is a traditional remedy used externally for skin infections, abscesses, and slow-healing wounds. It helps draw out toxins, dry oozing lesions, and promote tissue repair. It is also used internally for rheumatic joint pain and muscle aches.

TCM Properties

Temperature

Warm

Taste

Bitter (苦 kǔ), Sweet (甘 gān)

Channels entered

Liver, Spleen

Parts used

Resin / Sap (树脂 shù zhī / 汁 zhī)

Educational content Consult qualified TCM practitioners for diagnosis and treatment

What This Herb Does

Every herb has a specific set of actions — here's what Song Xiang does in the body, explained in both everyday and TCM terms

Therapeutic focus

In practical terms, Song Xiang is primarily used to support these areas of health:

TCM Actions

In TCM terminology, these are the specific therapeutic actions that Song Xiang performs to restore balance in the body:

How these actions work

Dispels Wind-Damp means Song Xiang eliminates wind and dampness from the channels and joints. This makes it useful for rheumatic conditions, muscle aches, and skin problems where wind and dampness are the main pathogens.

Dries Dampness refers to its ability to absorb excess moisture. It is particularly beneficial for weeping sores, oozing eczema, and any skin lesion with discharge.

Expels Pus describes its action of helping abscesses and boils mature and drain. It encourages the body to push out purulent material, speeding up resolution.

Draws Out Toxins means it can bring deep-seated toxins to the surface. This is critical for carbuncles and deep-rooted infections that are not coming to a head.

Promotes Tissue Regeneration indicates that it helps new flesh grow, aiding in the healing of wounds and ulcers.

Stops Pain reflects its analgesic effect, which can relieve the discomfort of sores, injuries, and joint pain.

Patterns Addressed

In TCM, symptoms cluster into recognizable patterns of disharmony. Song Xiang is used to help correct these specific patterns.

Why Song Xiang addresses this pattern

Song Xiang's bitter, warm nature and its strong ability to expel pus and draw out deep toxins make it suitable for the early stages of abscesses, carbuncles, and boils where toxic heat is localized and sluggish. It promotes suppuration and drainage, helping to resolve the stagnation and bring the lesion to a head, preventing the toxin from spreading deeper.

A practitioner would look for one or more of these signs

Carbuncles

localized red, swollen, painful lump with pus not yet formed or difficult to drain

Abscess

deep-seated infection with throbbing pain

Furuncle

single boil with a central core of pus

Commonly Used For

These are conditions where Song Xiang is frequently used — but only when they arise from the specific patterns it addresses, not in all cases

TCM Interpretation

In TCM, a carbuncle is seen as a localized accumulation of toxic heat and stagnant Qi and Blood, often deep in the tissues. The body's defensive Qi tries to wall off the pathogen, creating a swollen, painful mass that may fail to come to a head. This is a Toxic-Heat Stagnation pattern where the pathogen is trapped and needs to be drawn out.

Why Song Xiang Helps

Song Xiang's primary action of expelling pus and drawing out toxins directly addresses the stagnation. Its warm, penetrating nature helps to break through the blockage, encourage suppuration, and drain the toxic material. This action is why it is a key ingredient in many traditional plasters and ointments for stubborn abscesses.

Also commonly used for

Abscess

Helps ripen and drain pus, reducing swelling and pain.

Furuncle

Used externally to bring boils to a head and speed resolution.

Scabies

Kills parasites and dries dampness, reducing itching and crusting.

Ringworm

Antifungal and drying action helps clear scaly, itchy patches.

Traumatic Injury

Applied as a liniment to reduce swelling, bruising, and pain from sprains and contusions.

Wound Infection

Promotes tissue repair and prevents infection in slow-healing wounds.

Hemorrhoids

Used in suppositories or ointments to shrink swollen hemorrhoidal tissue and ease pain.

Herb Properties

Every herb has an inherent temperature, taste, and affinity for specific channels — these properties determine how it interacts with the body

Temperature

Warm

Taste

Bitter (苦 kǔ), Sweet (甘 gān)

Channels Entered

Liver Spleen

Parts Used

Resin / Sap (树脂 shù zhī / 汁 zhī)

Dosage & Preparation

These are general dosage guidelines for Song Xiang — always follow your practitioner's recommendation, as dosages vary based on the formula and your individual condition

Standard dosage

Internal: 3–5 g in decoction, or as pills/powders with wine. External: appropriate amount, ground and applied or mixed with oil.

Maximum dosage

Do not exceed 5 g per dose internally. Higher doses risk severe gastrointestinal irritation and systemic toxicity.

Dosage notes

Internal use is generally reserved for rheumatism, skin conditions, or leukorrhea, and always in a well-processed form. The dose for internal decoction is 3–5 g; for pill or powder forms, the daily dose can be adjusted within that range. External use has no strict limit, but excessive application on broken skin should be avoided due to potential absorption and toxicity.

Preparation

For decoction, wrap the resin in a cloth pouch to prevent it from sticking to the pot. Alternatively, it can be dissolved in warm wine and added to the strained decoction. For external use, the refined powder is often mixed with oils or made into a plaster after melting.

Common Herb Pairs

These ingredients are traditionally combined with Song Xiang for enhanced therapeutic effect

Ru Xiang
Ru Xiang 1:1 (often equal parts in external powders or plasters)

Song Xiang draws out toxins and expels pus, while Ru Xiang invigorates blood and relieves pain. Together they powerfully treat traumatic injuries, carbuncles, and sores, reducing swelling and accelerating healing.

When to use: For wounds, bruises, and abscesses with significant pain and blood stasis.

Mo Yao
Mo Yao 1:1

Similar to the pair with Ru Xiang, Song Xiang's pus-expelling and toxin-drawing action is complemented by Mo Yao's ability to break up blood stasis and reduce swelling. This pair is especially effective for chronic, hard, non-healing sores.

When to use: For stubborn ulcers, deep abscesses, and traumatic swelling that is slow to resolve.

Da Huang
Da Huang Song Xiang 3 parts : Da Huang 1 part (e.g., 30g : 10g for external paste)

Song Xiang's warm, drawing nature is balanced by Da Huang's cold, heat-clearing, and toxin-purging action. Together they address toxic-heat abscesses by both clearing heat and drawing out pus, preventing the infection from spreading internally.

When to use: For red, hot, painful carbuncles and furuncles in the early stage, especially when there is constipation.

Comparable Ingredients

These ingredients have overlapping uses — here's how to tell them apart

Xue Jie
Song Xiang vs Xue Jie

Both are resinous substances that promote tissue regeneration and stop bleeding. However, Xue Jie is neutral in temperature and primarily stops bleeding and resolves stasis, while Song Xiang is warm, dispels wind-damp, and draws out toxins. Song Xiang is better for deep abscesses and damp skin conditions; Xue Jie is preferred for bleeding wounds and blood stasis pain.

Er Cha
Song Xiang vs Er Cha

Both dry dampness and promote healing of sores. Er Cha is bitter, astringent, and cool, mainly used for weeping eczema and oral ulcers, with a stronger drying and astringent effect. Song Xiang is warm and more focused on drawing out toxins and expelling pus, making it better for deep-seated, stubborn abscesses.

Identity & Adulterants

Related species and common adulterations to be aware of when sourcing Song Xiang

Song Xiang is often used as an adulterant for the more expensive Ru Xiang (Frankincense). Its own substitution is less common, but industrial-grade colophony or chemically modified rosin can be passed off as medicinal grade. Adulteration with starch or other plant resins has been reported. Authentic medicinal Song Xiang should dissolve without residue in alcohol and give characteristic abietic acid peaks on HPLC/TLC analysis; iodine test can reveal starch contaminants.

Educational content — always consult a qualified healthcare provider or TCM practitioner before using any herb.

Toxicity Classification

Classical Chinese pharmacopoeia toxicity rating for Song Xiang

Slightly toxic

Song Xiang contains irritating volatile terpenes (α-pinene, abietic acid) that can cause skin and mucosal irritation, nausea, vomiting, and allergic dermatitis. Raw resin carries a higher risk. Traditional processing — melting, water-washing, and especially boiling with scallion (Cong Zhi Song Xiang) — removes much of the volatile irritants and reduces toxicity. The processed form is considered safe for short-term internal use at recommended doses.

Contraindications

Situations where Song Xiang should not be used or requires extra caution

Caution

Blood deficiency with internal heat signs — the herb's warm, drying nature can worsen Yin deficiency and fire.

Caution

Internal excess heat (实火) — the warm, drying action may exacerbate inflammatory conditions.

Caution

Prolonged internal use — may cause gastrointestinal stagnation and discomfort.

Avoid

Use of raw, unprocessed resin internally — high irritant content can cause severe gastrointestinal and mucosal damage.

Avoid

Known allergy to pine resin or colophony.

Avoid

Open wounds or extensive skin breaks — absorption of resin acids may cause systemic toxicity.

Special Populations

Important considerations for pregnancy, breastfeeding, and pediatric use

Pregnancy

Avoid use during pregnancy. The terpenoid constituents may cross the placenta and have unknown effects on fetal development. It is traditionally contraindicated in pregnancy due to its warm, dispersing nature and potential to disturb the fetus. Neither internal use nor prolonged, large-area topical application is recommended.

Breastfeeding

Avoid internal use during breastfeeding. Terpenoid compounds may be excreted in breast milk and their effects on infants are not well studied. Topical application on small, intact skin areas is likely low risk but should be done under guidance.

Children

Not recommended for internal use in children due to the herb's irritating nature and lack of safety data. External application should be limited on small, intact skin areas and only under professional supervision.

Drug Interactions

If you are taking pharmaceutical medications, be aware of these potential interactions with Song Xiang

Song Xiang may increase skin permeability when used topically, potentially enhancing the absorption and irritation of co-applied drugs such as camphor, menthol, or other resin-based salves. Use with caution alongside potent topical agents. Internal use of Song Xiang has mild platelet-inhibitory activity; concurrent use with anticoagulant or antiplatelet drugs (e.g., warfarin, aspirin) may theoretically increase bleeding risk. Monitor if such combinations are necessary.

Dietary Advice

Foods and dietary considerations when taking Song Xiang

Avoid cold, raw, and greasy foods, which can aggravate dampness and counteract the herb’s drying effects. When used externally for skin infections, avoid spicy, heating foods that may increase inflammation.

Botanical Description

Physical characteristics and morphology of the Song Xiang source plant

Song Xiang is obtained from several species of Pinus, notably Pinus massoniana Lamb. (马尾松) and Pinus tabuliformis Carr. (油松). These are large evergreen conifers reaching 20–45 m in height, with thick, reddish-brown bark that cracks into irregular, scaly plates. Needles are borne in bundles of two, slender, slightly twisted, 12–20 cm long, with finely serrated edges. The trees produce male and female cones; female cones mature into woody, ovoid structures 4–7 cm long. Resin ducts in the wood secrete an oleoresin that is harvested by cutting V-shaped or spiral grooves in the trunk. The trees thrive in mountainous regions and well-drained slopes, preferring warm temperate to subtropical climates.

Sourcing & Harvesting

Where Song Xiang is sourced, when it's harvested or collected, and how to assess quality

Harvesting season

Summer, when resin exudation is most abundant.

Primary growing regions

Guangdong, Guangxi, Fujian, Hunan, Jiangxi, Zhejiang, Anhui, and other southern provinces. Oil pine (P. tabuliformis) sources extend to Northeast, Northwest China, and Shandong.

Quality indicators

Good quality Song Xiang appears as irregular, semi-transparent blocks with a yellow surface often covered by a hoary white powder. It should be brittle at room temperature, with a glass-like, shiny fracture. A strong, characteristic pine-resin odor and bitter taste indicate freshness. The best grade is clean, uniform in size, highly oily, and intensely aromatic. Dull, dark, or crumbly pieces with weak odor are inferior.

Classical Texts

Key passages from the classical Chinese medical texts that describe Song Xiang and its therapeutic uses

《神农本草经》(Shen Nong Ben Cao Jing): “主痈疽恶疮,头疡白秃,疥瘙风气,安五脏,除热。”
(It treats carbuncles, malignant sores, scalp infections, favus, scabies, itching due to wind; settles the five zang organs and clears heat.)

《名医别录》(Ming Yi Bie Lu): “主胃中伏热,咽干消渴,及风痹死肌,炼之令白;其赤者主恶痹。”
(It governs latent heat in the stomach, dry throat, wasting thirst, and wind impediment with dead muscles. Refined until white it is used; the reddish resin treats severe impediment.)

Historical Context

The history and evolution of Song Xiang's use in Chinese medicine over the centuries

Song Xiang has been recorded in Chinese medical texts since the Shen Nong Ben Cao Jing (1st–2nd century CE), where it was classified as a top-grade herb. Its name literally means 'pine fragrance,' reflecting the aromatic resin. Throughout history, it was primarily used in surgery and dermatology for purulent skin infections due to its strong pus-drawing and tissue-regenerating actions. The famous Ming-dynasty physician Li Shizhen, in Ben Cao Gang Mu, documented it as 'Song Zhi' (松脂) and noted its ability to strengthen sinews and bones, treat leukorrhea, and sharpen hearing. The processing method using scallion juice to reduce toxicity was standardized by the Tang-Song period, reflecting a deep understanding of the need to refine the resin for internal safety.

Modern Research

A published study investigating the pharmacological effects or clinical outcomes of Song Xiang

1

Research Progress on the Biological Activities of Rosin Derivatives (2018)

Li Zhaoshuang, Li Jianfang, Liu He, et al. Chemistry and Industry of Forest Products, 2018, 38(3): 17-24.

A review summarizing the antibacterial, antifungal, anti-inflammatory, and antitumor activities of chemically modified rosin derivatives. Abietic acid and dehydroabietic acid showed significant antibacterial effects against Staphylococcus aureus including MRSA and Escherichia coli, partly by disrupting bacterial cell membranes. Anti-inflammatory action was linked to inhibition of NF-κB pathway and COX-2 expression.

Link

Research on individual TCM herbs is growing but still limited by Western clinical trial standards. These studies provide emerging evidence and should be considered alongside practitioner expertise.