As acupuncturists we have a wide range of tools at our disposal to aid in improving our treatment outcomes. Aside from the iconic acupuncture needle, moxibustion could be considered the philosophical Yang to the steel needle Yin of the craft. Its pungent smokey presence in our clinics speaks of ancient times when masters of the past would cure the ills of the sick and purge the prone of demonic possession (1:5).
While moxa is traditionally made from fermented Chinese mugwort (Artemisia argyi) (2:4), variations of the mugwort plant can be found in Europe (Artemisia vulgaris), Africa (Artemisia vulgaris), India (Artemisia vulgaris), and America (Artemisia douglasiana) (7:116). Chinese traditional uses include direct with cones made from leaf powder, or indirect with a stick made of leaves to heat the skin (7:118). Analogous moxa preparations are available today in all manner of forms from traditional to smokeless, and pharmacological studies have revealed the presence of more than 60 different components within the leaf (2:4).
It is suggested that moxibustion was more popular in ancient China as the early practice of acupuncture involved a less than calming process of bloodletting and incisions inflicted by the sharp end of stone needles or drainage by bian stones (1:2). Consequently, the abundant and easily cultivated mugwort (sometimes mixed with mulberry or peach tree branches) made for a far less intense and invasive treatment for a patient already in suffering (1:5). The first reliable written records of moxibustion can be traced back to the Warring States Period (475 BCE - 221 BCE) (3), however there is evidence to suggest that it may have been used as far back as the Yin Dynasty (1600 BCE - 1046 BCE) (1:1).
Moxibustion was such an integral aspect of the practice of acupuncture that the Chinese characters for acupuncture - 针灸 (zhēnjiǔ) actually translate to “acupuncture-moxibustion” (1:1). However the modern term ‘moxa’ that we use today is derived from the Japanese phrase ’moe kusa’ which means ‘burning herb’ (4). Evidence unearthed in ancient Chinese texts revealed the first indications for moxibustion were mainly associated with surgery involving traumatism, animal bites, purulent conditions, urinary and anorectal diseases (1:5).
Evolution of Chinese medicine saw its integration with the meridian system where it was used to warm the channels to nurture Yang and eliminate the cold of Yin, activate the acupuncture points and correct the disease state of the human body (2:2). Since the advent of Traditional Chinese Medicine (TCM) and scientific research, experts have investigated the effects of moxibustion for the treatment of 364 diseases with animal and human trials (1:5).
So what does this mean for us today as modern day acupuncture practitioners making use of an ancient form of treatment in the contemporary form? While the basis of moxibustion was to stimulate the meridians and bring warmth to the body (2:2), there are a number of complex chemical occurrences that underpin the mechanisms of the therapeutic effects of moxibustion on the body (2:4). And while a lucid presentation of the meridians themselves remains incomplete (1:1), there exists a wide body of evidence for the therapeutic effects of moxibustion.
Thermal Effects
The thermal effects of moxibustion influences both superficial and deep tissues of the skin and muscles which manifests as subjective heat, erythema, and sometimes even skin irritations or blisters (2:3). Vasoconstriction occurs at the burning point while around the point, vasodilation increases peripheral arterial blood flow and microvascular permeability (2:3). The stimulation of polymodal receptors (those that respond to multiple forms of stimuli such as heat, touch, chemicals etc.) within acupuncture points cause antipyretic and thermolytic effects (2:3).
A notably potent thermal effect of moxibustion is to stimulate the production and release of heat-shock proteins (HSP) in local tissues (2:3). HSPs play crucial roles in folding and unfolding proteins, assembly of multiprotein complexes, control and signaling of cell-cycles, transporting and sorting proteins into correct subcellular compartments, and the protection of cells against stress or cell death (apoptosis) (5). HSPs can stimulate important immune-system cells such as macrophages and dendritic cells (5).
Infrared Effects
Yet the effectiveness of moxibustion is not confined merely to its thermal effects alone. Burning moxa emits infrared (IR) and near infrared radiation (NIR) which may be an important aspect of its effectiveness (2:3). NIR transmits energy about 10 mm beneath the skin and induces active substances produced within the tissues that enhance the metabolism of organs and energise the metabolism of cells (2:4).
Pharmacological Effects
And finally, moxa smoke itself also appears to hold therapeutic properties with 26 ingredients being identified within it (2:4). Moxa smoke can be used as an air disinfectant and antifungal, with some reports suggesting that it could be beneficial in healing wound infections, vaginal itching and uterine prolapse, common warts and anal fistulas (2:5). One randomised controlled trial indicates that short-term exposure to moxibustion smoke may have positive regulating effects on human autonomic function when monitoring heart rate variability (6:9).
The volatile oil found within the moxa herb contains a variety of biological characteristics such as causing expansion of the smooth muscle of the airways and relieving cough, eliciting an expectorant effect, as well as having strong antioxidant properties (2:4). The use of garlic and ginger as intermediaries between moxa and skin have also been found to exert therapeutic effects by the release of their active components, gingerol and allicin respectively, in response to the heat of the moxa (2:4).
Conclusion
Practitioners of ancient China had certainly developed a formidable form of therapy to complement the once primitive practice of acupuncture. And although its therapeutic properties have been well-known for thousands of years, it is with the scrutiny of modern science that we are able to appreciate the full extent of its profound healing effects on the body. While a perspicuous explanation for the meridians may still elude us, the physiological mechanisms of certain aspects of TCM such as moxibustion can now be understood with a degree of clarity based on the evidence of scientific research.
References
Huang C., Liang J., Han L., Liu J., Yu M. & Zhao B. (2017) Moxibustion in Early Chinese Medicine and Its Relation to the Origin of Meridians: A Study on the Unearthed Literatures. Evidence-Based Complementary and Alternative Medicine. Vol. 2017. Viewed 10 March 2021. Source.
Deng H. & Shen X. (2013). The Mechanism of Moxibustion: Ancient Theory and Modern Research. Evidence-Based Complementary and Alternative Medicine. Vol. 2017. Viewed 10 March 2021. Source.
Zhang R. (2004). History and current state of moxibustion. Zhong Xi Yi Jie He Xue Bao. Vol. 2. Issue 6. pp. 466 - 73. Viewed 10 March 2021. Source.
Public domain - Google etymology search on origins of ‘moxa’
Li Z. & Srivastava P. (2004). Heat-shock proteins. Current Protocols in Immunology. Viewed 10 March 2021. Source.
Cui Y., Zhao B., Huang Y., Chen Y., Liu P., Huang J. & Lao L. (2013). Effects of Moxa (Folium Artemisiae argyi) Smoke Exposure on Heart Rate and Heart Rate Variability in Healthy Young Adults: A Randomized, Controlled Human Study. Evidence-Based Complementary and Alternative Medicine. Volume 2013. Viewed 10 March 2021. Source.
Adams J., Garcia C. & Garg G. (2012). Mugwort (Artemisia vulgaris, Artemisia douglasiana, Artemisia argyi) in the Treatment of Menopause, Premenstrual Syndrome, Dysmenorrhea and Attention Deficit Hyperactivity Disorder. Chinese Medicine. Vol. 3. pp. 116 - 123. Viewed 19 March 2021. Source.