Of all the ingredients listed on the label of a high-end Chinese medicated oil or plaster, none carries more cultural weight than 麝香 (She Xiang, “Musk”). It sits at the top of the aromatic-resuscitation (kai qiao) category in the Chinese Materia Medica, has been priced by weight against gold for most of the last millennium, and its presence on a tube of She Xiang Hu Gu Gao (Musk Tiger Bone Plaster) or a bottle of She Xiang Feng Shi You (Musk Rheumatism Oil) is the single strongest signal a Chinese consumer reads for “premium grade.” The biology behind that reputation is more specific than romance: musk’s principal active, muscone (3-methylcyclopentadecanone), is a macrocyclic ketone that does two pharmacologically distinct things at once — it suppresses the NF-κB / NLRP3 inflammatory axis at the cellular level, and it disrupts the lipid packing of the stratum corneum, dragging every other ingredient in the formula deeper into the skin than they could travel alone. This article unpacks the chemistry, the mechanism, the CITES-driven shift from natural to artificial musk, and what the label “含麝香” (contains musk) actually means on a modern bottle.

What She Xiang Is — Zoological and Botanical Identity

She Xiang is not a plant. It is the dried glandular secretion from the preputial sac of the male musk deer (genus Moschus), a small solitary ungulate found in the high alpine forests of the Himalayas, the Tibetan plateau, and the mountains of western and northeastern China. The 2020 edition of the Chinese Pharmacopoeia recognises three source species: Moschus berezovskii (Forest Musk Deer, 林麝), Moschus sifanicus (Alpine Musk Deer, 马麝), and Moschus moschiferus (Siberian Musk Deer, 原麝). The musk is harvested during the rutting season, when the gland produces a dark, waxy, granular substance with an intensely animalic-sweet odour. Traditional grading distinguishes “毛壳麝香” (whole-pod musk) from “麝香仁” (shelled musk kernel), with the kernel commanding the higher price.

In Chinese medical theory, She Xiang is classified as pungent, warm, and aromatic, entering the Heart and Spleen meridians. Its core action is “开窍醒神” — opening the orifices and rousing the spirit — which in clinical practice covers loss of consciousness from stroke, febrile delirium, and shock. A second, equally important action is “活血通经, 消肿止痛” — invigorating blood, freeing the channels, dispersing swelling, and relieving pain. It is this second action, combined with its extraordinary penetrating quality, that explains why musk became the signature ingredient of premium medicated plasters and trauma oils.

Chemical Composition — Beyond Just Muscone

Although muscone is the molecule that gets the headlines, natural musk is a complex matrix. Modern analytical work identifies several pharmacologically active classes:

Crucially for transdermal medicated formulations, muscone itself is a lipid-soluble small molecule (molecular weight 238.4 g/mol, logP ~ 5.5) — small enough and lipophilic enough to dissolve into the stratum corneum and partition across it readily.

Pharmacology #1 — Muscone as an Anti-Inflammatory Macrocyclic Ketone

In the last decade, muscone has gone from a “traditional ingredient with vague effects” to a molecule with a defined mechanism. Multiple in vivo and in vitro studies converge on the same picture:

NF-κB pathway inhibition. Muscone significantly downregulates LPS-induced activation of NF-κB in macrophages, with downstream reduction in the inflammatory cytokines IL-1β, TNF-α, and IL-6. In a 2019 myocardial infarction model, oral muscone at 2 mg/kg/day for three weeks improved cardiac function and survival, with the effect explicitly traced to suppression of NF-κB and the NLRP3 inflammasome in cardiac macrophages.

NLRP3 inflammasome suppression. Muscone inhibits assembly of the NLRP3 inflammasome, the upstream switch that converts the inactive pro-form of IL-1β into mature, secreted IL-1β. This is the same axis targeted by colchicine and the IL-1β antibody canakinumab, which gives a sense of the scale of the effect when muscone is delivered at sufficient concentration locally.

TREM-1 and TRAF6 downregulation. Muscone inhibits TREM-1 (Triggering Receptor Expressed on Myeloid cells 1) and disrupts TRAF6 binding to RANK, suppressing both NF-κB and MAPK pathways. In ovariectomy-induced bone loss models, this translates into reduced osteoclastogenesis — a finding that gives some pharmacological backing to musk’s historical use in trauma and orthopaedic formulas alongside ingredients like tu bie chong and zi ran tong.

For a topical medicated oil, the relevant question is not whether muscone can reach systemic targets — it usually cannot in pharmacological quantities through a single application — but whether the local concentration in inflamed dermis and subcutaneous tissue is enough to suppress the local cytokine signal driving pain. The accumulating evidence is that, for ankle sprains, contusions, and arthritic joint flares, that local effect is real and measurable.

Pharmacology #2 — Muscone as a Transdermal Penetration Enhancer

This is the property that ties the whole TCM theory of musk together. Classical external-medicine texts said musk had the ability to “通经络, 透肌骨” — pass through the channels and penetrate flesh and bone — and that it could “引诸药直达病所” — guide the other drugs directly to the site of disease. Translated into modern terms, this is a description of a penetration enhancer.

Modern dermatopharmacology has confirmed exactly that role. The stratum corneum, the outermost 10–20 μm of dead keratinocytes embedded in an organised lipid matrix of ceramides, cholesterol, and free fatty acids, is the principal barrier to topical drug delivery. Muscone, by virtue of its high lipophilicity and macrocyclic structure, partitions into this lipid matrix and disrupts its tight lamellar packing. The result is a measurable increase in the flux of co-administered drugs across the skin. Published studies have demonstrated muscone-mediated enhancement of transdermal permeation for drugs across a wide range of lipophilicities, including water-soluble actives that would otherwise barely cross at all.

This dual identity — anti-inflammatory cargo AND penetration enhancer for the rest of the formula — is what makes musk so structurally important in a classical medicated oil. When borneol, camphor, and musk appear together at the top of an ingredient list (as they do in An Gong Niu Huang Wan and most premium liniments), the implicit pharmacological design is: borneol and camphor open the surface and create a counter-irritant cooling sensation, musk drives everything else deeper, and the remaining herbs — hong hua, xue jie, ru xiang, mo yao — get to do their work in the actual injured tissue rather than evaporating off the skin surface.

The CITES Question — What “Contains Musk” Means in 2026

Natural musk has been listed under CITES Appendix II (and Appendix I for several populations) since 1979. Wild populations have collapsed across most of the historical range; legal supply now comes almost exclusively from licensed musk deer breeding farms in Shaanxi, Sichuan, and Anhui, where musk can be milked from live males without slaughter. The legal natural-musk supply is small, expensive, and tightly controlled, and the great majority of it is reserved for a short list of state-protected flagship TCM preparations — She Xiang Bao Xin Wan, An Gong Niu Huang Wan, Pian Zai Huang, Liu Shen Wan, and a few others — under the “国家保密配方” (state secret formula) framework.

Everything else — including the overwhelming majority of musk-branded medicated oils and plasters on the market — uses artificial musk (人工麝香, Ren Gong She Xiang), an industrially produced substitute developed by a Chinese national research project in the 1980s–1990s and approved as a Class I new drug in 1994. Artificial musk is a defined multi-component formulation that includes synthetic muscone, muscopyridine analogues, and chemically reconstituted steroidal components. Multiple comparative studies have shown that artificial musk reproduces the anti-inflammatory, analgesic, and resuscitative actions of natural musk closely enough to serve as a 1:1 substitute in most preparations, and as of 2026 it is the form used in essentially every consumer-grade medicated oil sold under a “麝香” name.

A practical consequence for buyers: a bottle of medicated oil labelled “麝香风湿油” or “麝香舒活油” at a normal consumer price almost certainly contains artificial musk, not natural musk. This is not adulteration — it is the regulatory standard. Natural musk at retail would put a single 50 ml bottle into the four-figure US-dollar range. Authenticity testing in the published literature now uses GC-MS profiling of muscone alongside steroid markers precisely because muscone alone cannot distinguish natural from synthetic; only the steroid fingerprint and the polypeptide profile can.

For the consumer, the practical implication is that the pharmacological activity is largely preserved in the artificial form for analgesic and anti-inflammatory purposes. What is lost is the polypeptide-mediated effects (most relevant to cardiovascular indications) and, depending on personal aesthetics, some of the depth and complexity of the odour.

Where You Actually Encounter She Xiang in Medicated Oils

Musk-bearing topical products fall into several archetypes:

Safety, Contraindications, and Practical Use

Pregnancy is the single hard contraindication. Classical Chinese medicine considers musk strongly po xue — blood-breaking — and warns explicitly against use in pregnancy because of the historical association with abortifacient effects. This warning extends to topical use of musk-containing medicated oils and plasters, particularly over the abdomen and lower back. The mechanism is not fully resolved but appears to involve uterine smooth-muscle stimulation; in pregnancy, avoid all musk-bearing topicals, including artificial musk preparations, as a precaution.

Broken or weeping skin. Because musk enhances the penetration of every other ingredient in the formula, applying a musk-containing oil to open wounds, severe eczema, or weeping dermatitis dramatically increases the systemic absorption of co-formulated camphor, methyl salicylate, and menthol. This is the same penetration-enhancer logic that makes musk useful in intact-skin applications turning against the user when the barrier is compromised.

Drug interactions. Documented clinically meaningful interactions for topical musk preparations are rare in the literature, but the penetration-enhancer effect implies that any drug interactions of the co-formulated ingredients — particularly methyl salicylate with anticoagulants — are amplified rather than diminished. Patients on warfarin or direct oral anticoagulants who use musk-containing salicylate plasters over large body areas should be monitored.

Children. Musk-containing oils and plasters are traditionally avoided in infants and young children. The combination of high penetration with potent co-actives (camphor, methyl salicylate) makes the pediatric risk-benefit unfavourable, and pediatric formulas like Yu Yee Oil deliberately omit musk for this reason.

Olfactory caution. Even artificial musk produces an intense, persistent odour that can trigger headache or nausea in sensitive individuals and that will linger on clothing and bedding. Patch-test a small area before extended use.

How to Read a Musk-Labelled Bottle in 2026

A practical decoding guide for the modern shelf:

The bottom line: musk has earned its mythic status in the Chinese medicated-oil tradition, but the version in your hand in 2026 is almost certainly the synthetic. That is not a downgrade — it is a CITES-aligned, pharmacopoeia-validated, mechanistically equivalent substitute for the analgesic and penetration-enhancing actions that matter most in a topical setting. The deer survive. The pharmacology persists. The label endures.

Further Reading

Sources: Pharmacological effects and mechanisms of muscone (Journal of Ethnopharmacology, 2020); Zoology, chemical composition, pharmacology, quality control and future perspective of Musk (Moschus): a review (Chinese Medicine, 2021); Muscone improves cardiac function in mice after myocardial infarction by alleviating cardiac macrophage-mediated chronic inflammation through inhibition of NF-κB and NLRP3 inflammasome (PubMed, 2019); Investigation of muscone as transdermal penetration enhancer (Journal of Drug Delivery Science and Technology, 2021); Chinese Pharmacopoeia 2020 edition, monograph on Moschus; From non-targeted to targeted GC–MS metabolomics strategy for identification of TCM preparations containing natural and artificial musk (PMC, 2022).