Fire is Equal to the Task

Warming treatment strategies with moxibustion

fire kidney, water kidney

Moxibustion has several aspects which may contribute to its clinical effects. Wu et al. (2013) identify three basic factors involved in moxibustion: thermal stimulation, light radiation, and by-products of combustion (smoke, ash, aroma). Of these three, the thermal effects, i.e. warmth and heat, are perhaps the most characteristic; there are a variety of devices which limit or eliminate the smoke and ash and restrict the light radiation of burning moxa, but almost all of them (save some of the topical moxa products that are available) utilize the physical property of warmth.

Warming is one of the eight methods of herbal medicine, and presents a natural link between treatment strategy of Chinese medicinal therapy and acumoxa therapy. I recently ran across a paper by Zhang et al. (2012) published in the journal Chinese Acupuncture & Moxibustion [中国针灸] on both practical and theoretical elements of warming moxibustion. I read the piece with great interest, as it centered on comparisons with the warming schools of herbal medicine. My intent with this post is to provide a sort of article review, summarizing some of its main points here, with reference to a few other sources as well.

Warming and its physical effects

In the paper, Zhang et al. (2012) start out by laying out some parameters for warm [versus hot] moxibustion. Various methods of moxibustion exist and they may be employed in different situations with distinct outcome measures associated with each, for example local skin flushing may suffice or suppuration and scarring may be required. In terms of the sensation provoked by moxibustion, generally it begins with warmth and then may progress to hot, then scorching, and painful. Each of these has different effects, including various endogenous chemical reactions at certain temperatures.

 Thermal skin receptors can differentiate four primary types of temperature: warm, hot, cool and cold. This basic sensory gradation occurs within a fairly narrow range of 15°-43°C. Anything outside of that range evokes pain along with the perception of temperature, and that pain generally signals tissue damage (Zhang et al., 2012).

So when discussing the techniques described in the previous post as warm mild moxibustion, circular and sparrow-pecking moxibustion – methods which avoid the generation of suppurating sores and scars - we are discussing techniques in which the skin temperature does not reach much above 43°C. There is some variance to this number in  the literature: Wang et al. (2023) center the upper end of the spectrum at 44°C±1, and Zhao et al. (2016) cite research for various biochemical effects of suspended moxibustion up to 46°.

In practical application, based on the sources I have read, I would say that the moving forms of suspended moxibustion – circular, ironing, sparrow-pecking – would generally utilize the upper few degrees of this range; if the moxa stick were stationary, the temperature perception would register as hot to the patient, and the continual motion of the stick in these methods is key to avoiding tissue damage. Warm-mild moxibustion, being a still technique, should be perceived as warm and not painful.

Warming as a treatment principle

Warming is an important treatment principle in Chinese medicine. The idea of warming yáng is fundamental to the early classics like Huángdì Nèijīng [Yellow Emperor’s Inner Classic] and Shānghán Lùn [Treatise on cold damage]. Entire schools of practice have been founded on the doctrine of warming. Zhèng Qīn'ān 鄭欽安 , noted proponent of the yang-supporting school [扶陽派 fúyáng pài] is credited with the axiom：“火盛則水盛，火衰則水衰。” “When fire is exuberant, then water is exuberant, when fire is debilitated, then water is debilitated" (Fan et al., 2024).  [Zhèng Qīn'ān is best known in the West as the progenitor of the Fire Spirit School.]

Zhang et al. (2012), writing about moxibustion, and Fan et al. (2024), writing about medicinal therapy, both point to two major warming strategies in Chinese medicine: warming and freeing [溫通 wēntōng], and warming and supplementing [溫補 wēnbǔ].

Warming and freeing in moxibustion

According to Zhang et al. (2012), warming and freeing means using warmth to free [通tōng, also translated as unblock], and freeing means principles such as

• freeing and facilitating [通暢 tōngchàng]

• freeing and outthrusting [通達 tōngdá]

• freeing and regulating [通調 tōngtiáo]

Moxa’s warming and freeing effect, when applied to specific areas and acupoints, in turn can engender a number of different actions:

• scatter cold [散寒 sànhán]

• clear heat [清熱 qīngrè]

• course wind [疏風 shūfēng]

• dispel dampness [祛濕 qūshī]

• quicken blood [活血 huóxuè]

• transform stasis [化瘀 huàyū]

• draw toxin [拔毒 bádú]

• disperse binds  [散結 sànjié]

• effuse sweat [發汗 fāhàn]

• disinhibit water  [利水 lìshuǐ]

• disperse swelling [消肿 xiāozhǒng]

• relieve pain [止痛 zhǐtòng]

• regulate fat [调脂 tiáozhī]

• alleviate impediment [蠲痹 juānbì]

Zhang et al. (2012) cite modern master Hè Pǔrén [賀普仁] (1926-2015), who stated that moxibustion’s main mode of action was "to warm yáng and dispel cold, to course and free qì and blood" [“温陽祛寒、疏通氣血”]; thus Hè classified it in the category of warming and freeing methods.

Warming and freeing can include strong and weak methods together with fast and slow methods. Generally in cases where there is blockage due to stagnation of the channels and networks, the qì and blood are not able to flow and the situation will be urgent and severe, the situation requires a strong amount of heat for a more immediate effect. In cases of phlegm turbidity, stasis and stagnation, with chronically inhibited flow of qì and blood, the amount of heat can be small, to slowly warm over time, with the aim of a cumulative effect (Zhang et al. 2012).

Warming and freeing in Chinese herbal medicine

Fan et al. (2024) associate the strategy of warming and freeing with the Shānghán Lùn [Treatise on Cold Damage], which employs many medicinals and prescriptions with pronounced warm, hot and acrid properties to resolve the exterior and effuse sweat or to warm the interior and dispel cold evil, usually in decoctions with relatively few ingredients in large doses for quick effects.

Though the analogy here between the actions of the herb prescriptions and those of the moxibustion seem rather obvious, Zhang et al. (2012) argue that the effects of moxibustion with regard to warming and freeing are essentially distinct from the warming and freeing prescriptions of Chinese herbal medicine. Moxibustion, the authors say, uses physical heat in order to warm the yáng and promote the flow of qì and blood, where warming prescriptions use medicinal agents with warming properties to dispel yīn evils and dispel cold. Moxibustion can not only warm yáng and dispel cold, they state, it can discharge heat to the exterior [引热外泄], draw toxins and disperse binds, and thus its range of functions is wider than that of warming and unblocking medicinals.

Warm supplementation in moxibustion

According to Zhang et al. (2012), supplementing includes principles such as

• supplementing and assisting [補助 bǔzhù]

• supplementing and boosting [補益 bǔyì]

• supplementing and filling [補充 bǔchōng]

When the warmth of moxibustion is applied to certain areas of the human body, (i.e. acupuncture points) , it can supplement and boost the qì and blood of the human body and enhance its functioning .

The idea of warming supplementation has its origins in the classics. Líng Shū (Spiritual Pivot) 73 states “if yīn and yáng are both vacuous, fire is equal [to the task].” [“陰陽皆虚, 火自當之”], and “if there is sinking downward, use moxibustion” [“陷下則灸之”]. Thus Zhang et al. (2012) state that moxibustion can be used in any vacuity whether yáng or yīn, qì or blood. Moxa works by means of supporting yáng and supplementing qì [扶陽補氣], and when yáng arises yīn grows [陽生陰長]. Essentially, warm supplementing moxibustion rallies the yáng qì to enrich and nourish yin-blood.

Zhū Dānxī [朱丹溪] in Dān Xī’s Heart Methods [朱丹溪心法, Dānxī  Xīnfǎ] wrote:

“in severe illness with vacuity desertion, the root is yáng vacuity; use moxibustion at the dāntián so that the yáng is supplemented, and therefore when yáng arises yīn grows” [“大病虚脱，本是陽虛，用艾灸丹田者，所以虛陽，陽生陰長故也”]  (Zhang et al., 2012) .

Zhang et al. (2012) summarize by saying that by using appropriate stimulation via moxibustion on specific body areas (acupoints) , for disease conditions related to yáng qì vacuity debilitation and yīn blood insufficiency, moxibustion can engender and support yáng and supplement qì, and through the clinical effects of “yáng arises, yīn grows”, exert a broad spectrum of supplementation effects to both yáng and yīn aspects of the body.

Specific supplementing effects of moxibustion mentioned in the paper include:

• returning yáng [回陽 huíyáng]

• upbearing yáng [升陽 shēngyáng]

• enriching yīn [滋陰 zīyīn]

• engendering blood [生血 shengxuè]

• fortifying the spleen [健脾 jiànpí]

• boosting the kidney [益肾 yìshèn]

As with the warming-freeing principle, Zhang et al. (2012) also differentiate between strong/weak and slow/fast in warm supplementation with moxibustion. In cases of separation-expiry of yīn and yang, fulminant yáng qì desertion, and critically ill patients with  desertion pattern manifestations such as streaming sweat, reversal cold of the four limbs, and faint pulse verging on expiry, heavy amounts of moxibustion and urgent supplementation is necessary; for patients with simple vacuity debilitation, or when yīn and yáng are both vacuous, one can use smaller amounts of moxibustion to slowly warm, with a focus on the cumulative effects over time.

Warm supplementation in Chinese herbal medicine

According to Fan et al. (2024), warm supplementation as a current of thought developed later, evolving in part from the supplementing earth theories of Lǐ Dōngyuán [李東垣]. Lǐ used warm sweet medicinals in small amounts in many of his formulas. In the Ming era, physicians such as Xuē Jǐ [ 薛己] and Zhào Xiànkě [趙獻可] used approaches that combined both earth-supplementing, nourishing the kidneys, and boosting the gate of life. The development of the warm supplementing school is also associated closely with Zhāng Jǐngyuè [張景岳], who gave us such formulas as Zuǒguī wán [Left-Restoring Pill] and Youguī wán [Right-Restoring Pill]. Warming and supplementing prescriptions are better suited to chronic cases and older or more debilitated patients than warming and freeing prescriptions; warm supplementation tends to employ pills with more ingredients at smaller dosages for slower more gentle effects (Fan et al., 2024).

Zhang et al. (2012) point out that moxibustion’s warm supplementing properties and the warm supplementation doctrine of Zhāng Jǐngyuè have some essential differences, much as in the case with warming and freeing strategies. Moxibustion’s warm supplementation has a physical nature, where the warm supplementing formulas and medicinals are based on the warming natures of the substances in the materia medica; both cannot be regarded as the same.  Insufficiencies of the human body, the authors write, do not reach beyond yīn vacuity (which includes blood vacuity), yáng vacuity (which includes qì vacuity), and dual yīn and yáng vacuity. So the treatment methods in herbology require supplementing yīn in yīn vacuity, supplementing yáng in yáng vacuity, supplementing both yīn and yáng in dual yīn-yáng vacuity, with corresponding prescriptions and medicinals of the types that enrich yīn and supplement blood, warm yáng and supplement qì. Zhāng Jǐngyuè’s warm supplementation doctrine, the authors state, is chiefly yáng warming prescriptions and medicinals corresponding to patterns of yáng qì insufficiency. In contrast, moxibustion can more generally treat both yáng and yin, per the previously stated passage from Líng Shū that “if yīn and yáng are both vacuous, fire is equal [to the task]” and thus is suited to treat both yīn vacuity and yáng vacuity. Moxibustion warm supplementation’s functional scope compared to the warm supplementing prescriptions and medicinals is broader, in that it can not only support yáng and supplement qi, but it can through the principle of “yáng arises, yīn grows” be useful in yīn blood insufficiency.

Zhang et al. (2012) cite this quote from Luó Tiānyì [羅天益] (1220-1290), which elucidates both moxibustion’s supplementing action and its mobile nature:

 “欲得生精要補虛，先灸中脘，乃胃之經也，使引清氣上行，肥腠理；又灸氣海，乃生發元氣，滋榮百脈，長養肌肉；又灸三里，為胃之合穴，亦助胃氣撤上热，使下于陰分’（羅天益《衛生寶鑒》)

"Should you wish to nourish essence and to supplement vacuity, first apply moxibustion to Zhōngwǎn [CV12] which is the channel of the stomach, to lead the clear qì upward, to the fat and striations [còulǐ]; then moxa Qìhǎi [CV6] to increase the original qì, enrich the provisioning in the hundred vessels, and grow and nourish the flesh and muscles; then moxa Sānlǐ [ST36], which serves as the uniting [hé] point of the stomach, to also help the stomach qì to remove heat from the upper [burner] and descend it to the yīn aspect."

Luó Tiānyì, Precious Reflections on Guarding Life [衛生寶鑒 Wèi Shēng Bǎo Jiàn] c.1281

Both ends of the spectrum

Of course, pathomechanisms involving vacuity and repletion can be mutually engendering. Qì and blood vacuity can lead to insufficient flow, which can develop into blockage in the channels and networks; qì and blood stasis can cause obstruction in the channels and networks which prevents provisioning qì from reaching the viscera, thus leading to a state of vacuity. Moxibustion can help resolve these conditions from either end of the spectrum. By warming and freeing the circulation of qì and blood, it can reduce and eliminate obstructions in the channels and networks, thus allowing nourishment to reach the organs. By warming and supplementing yáng qi, it can invigorate the flow of qì and blood to prevent stasis, and by the mechanism of yáng arises and yīn grows, it can help enrich yīn blood and boost its ability to nourish the organs.

Conclusion

To summarize, moxibustion can make a natural link with warming strategies in Chinese herbal medicine, but moxibustion is also broader in its scope of action. Combining the warmth of moxibustion with the actions and indications of particular points can add specificity to its effects. In my mind, with regard to techniques of suspended (moxa stick) moxibustion, the indications for circular, spiraling, ironing, and sparrow-pecking moxibustion techniques can be seen to correspond more closely with the various principles associated with warming and freeing; the mild warming suspended moxibustion technique is more closely aligned with warming supplementation.

That’s it for now, thanks for reading.

---

Note: this publication is for information purposes only and is not intended as medical advice. Please seek the opinion of a health care professional for any specific medical issues you may have.

References

Fan, J.J., Wei, X.D., Zhang, H.Q., Zhang, F., Cheng, C., Li M.J., & Wang, P. (2024). Differentiation and analysis of theory of warming-dredging and warming-tonifying. Journal of Shandong University of Traditional Chinese Medicine, 48(3),300-304. DOI：10.16294/j.cnki.1007-659x.2024.03.007

Wang, Q.M., Gao, M., Li, S.X., Wang, B., Xu G., & Wen, J.L. (2023). Effect of mild moxibustion with moxa stick and infrared mild moxibustion on skin blood perfusion at Waiguan（TE 5). Chinese Acupuncture & Moxibustion, 43(11), 1269-1274. DOI: 10.13703/j.0255-2930.20221115-k0001

Wu, H.J, Ma, X.P., Zhou, Z.L., Bao, C.H., & Dou, C.Z. (2013). Current status and strategic thinking of moxibustion research. World Traditional Chinese Medicine, 8(8), 846-861. doi: 10.3969/j.issn.1673-7202.2013.08.001

Zhang, J.B., Wang, L.L., Wu, H.G., Hu, L., Chang X.R., Song, X.G., Ma X.P.（2012). Theory study: Warming-dredging and warming-reinforcing of moxibustion. Chinese Acupuncture & Moxibustion, 32(11), 1000-1003. DOI:10.13703/j.0255-2930.2012.11.016

Zhao, M., Li, H., Wu H.J., Zhang, J.B., Huang, Y., Bao, C.H., Dong, H.S., Wu, R.Z., Chen, P.S., & Li, J. (2016). How to improve the clinical efficacy of moxa stick suspension moxibustion. World Chinese Medicine, 11(12), 2539-2548. doi:10.3969/j.issn.1673-7202.2016.12.007