Moxa Cone Therapy

Early textual records

Moxibustion appears in some of the earliest surviving Chinese medical writing. A 2017 review of bamboo and silk texts reports that the Mawangdui manuscripts, from a tomb dated to 168 BCE, are among the earliest monographs that cover both the vessels that later became the meridians and the use of moxibustion on them. The review says moxibustion was the only therapy described for most of the diseases in these books. It also notes that studies of Oracle Bone Script suggest moxibustion might have been applied during the Yin dynasty, 1600 to 1046 BCE.

The same review describes several modalities in these texts, including fume moxibustion, direct moxibustion and what it calls natural moxibustion, in which irritant substances such as white mustard seed are applied to the skin to raise a blister. The moxa stick, now the most common form in clinical use, does not appear in the earliest texts the review examined. Its earliest record that the review cites comes from a later period. The review's account rests on scholarly interpretation of partly damaged texts, and it notes that character meanings have changed over time.

Development and the moxa cone

By the later periods the review describes, moxibustion had been developed into several modalities, and different diseases were treated with different materials and methods. Early practitioners used moxa floss made from processed mugwort leaves, which the review regards as more suitable than other combustible materials. The texts also set rules about timing, body region and aftercare.

Some early rules rested on beliefs that the review describes as demonological and that modern studies cannot validate, such as age-based restrictions on treating particular body regions. The review also records that a sore following strong scarring moxibustion was regarded as close to inevitable, and that early texts gave advice on treating such sores. The review presents these passages as historical texts and does not treat them as current guidance.

Cone, stick and floss

Moxa cone therapy refers to moxibustion performed with a small, shaped cone of moxa placed on or near an acupoint. Moxa is made from dried mugwort, a plant in the Artemisia genus, and a Cochrane abstract on moxibustion for cancer-treatment side effects describes the herbal material as containing Artemisia vulgaris. The cone is distinguished in the literature from the moxa stick, which is held above the skin in indirect forms of treatment.

The labels are not always kept apart. The same Cochrane review of cancer-treatment side effects included both moxa cone and moxa stick trials under the single term moxibustion. Where a study does not name the form used, a reader cannot tell whether cones, sticks or another device were applied, so the label moxa cone should be used only when a source names it.

Direct and indirect variants

Xu and colleagues define direct moxibustion as a cone placed directly on the skin and ignited, and indirect moxibustion as a cone or stick kept at a distance from the skin, with an insulating material between them. The insulating materials they list include air, garlic, ginger, aconite and salt.

The distinction matters for how harms are understood. Xu and colleagues attribute burns from direct moxibustion to contact with combustion products and burns from indirect moxibustion to radiant heat. The overview of knee osteoarthritis reviews lists traditional, indirect, heat-sensitive and thunder-fire moxibustion as variants of a non-invasive category, which shows how broadly the word moxibustion is used.

Setting and the moxa cone

Moxa cone therapy is usually delivered by a practitioner trained in East Asian medicine, in a clinic or practice setting. The practitioner selects acupoints according to the framework the practitioner uses. The overview of knee osteoarthritis reviews describes the traditional view that moxibustion works through meridians and moxa fire. Case reports in the safety review also describe self-administered moxibustion at home, and the same review identifies practitioner proficiency as a factor in safety.

A cone can sit on the skin itself, or a separating layer can lie between the cone and the skin. Many trials do not report the size of the cone, the distance from the skin or the number of cones applied, so the reviews cannot describe a standard procedure. Practitioners and participants may notice smoke and warmth. A 2017 review cites a 2000 study in which 733 of 829 patients reported a sensation travelling along a line that matched a meridian during treatment.

What participants may notice

Warmth, redness, itching and skin flushing are the effects most often mentioned in the reviews. The knee osteoarthritis overview lists rubefaction, blistering and skin flushing among the discomfort reported in trials, while the allergic rhinitis review names burns and blisters as the main adverse reactions reported for indirect moxibustion.

Xu and colleagues write that improving practitioner skill and regulating operations may reduce adverse reactions. Park and colleagues state that the incidence of moxibustion adverse events is not known. A person considering the practice therefore cannot take the reviews as evidence that a given session will be free of effects, and it is reasonable to ask a practitioner how the treatment will be applied and what reactions to watch for.

Conditions that have been studied

Research on moxibustion has concentrated on a small number of conditions. Breech presentation has been studied because moxibustion at Bladder 67 (BL67), a point at the tip of the fifth toe, is used to try to turn a breech baby before labor. Knee osteoarthritis, side effects of cancer treatment and allergic rhinitis have also been studied.

The knee osteoarthritis overview describes a traditional view that moxibustion works through meridians and moxa fire. It also notes that the analgesic mechanism may involve thermal, radiant and pharmacological effects of moxibustion and its smoke. These are proposed mechanisms. The overview does not treat them as proof of a clinical benefit.

Claims the sources do not support

The sources reviewed do not support a general claim that moxa cone therapy treats or prevents disease across the board. Findings for breech presentation do not transfer to pain, findings for knee osteoarthritis do not transfer to cancer side effects, and findings for allergic rhinitis do not transfer to any of these, because each review asks a different question in a different population against a different comparator.

Historical sources describe moxibustion as a principal therapy in earlier periods. The 2017 review of unearthed texts records a link between moxibustion and the development of meridian theory, but it presents this as a hypothesis supported by hints rather than a settled conclusion.

Breech presentation

Coyle and colleagues' 2012 Cochrane review, in its updated form, included eight randomized trials with 1,346 women. It found that moxibustion did not reduce the number of non-cephalic presentations at birth compared with no treatment. Women who had vaginal births used less oxytocin before or during labor (risk ratio 0.28, 95% confidence interval 0.13 to 0.60). The review concluded that the evidence is limited.

Vas and colleagues' 2009 meta-analysis of six studies with 1,087 participants reported cephalic presentation at birth in 72.5% of moxibustion groups and 53.2% of control groups (relative risk 1.36). Its authors urged caution because of heterogeneity. Liao and colleagues' 2021 update of 16 randomized trials with 2,555 participants reported a relative risk of 1.39 for cephalic presentation, with a larger estimate in Asian populations (1.42) than in non-Asian populations (1.20).

The pooled estimates differ between reviews, and the trials differ in comparators and quality, so the breech evidence should be read as mixed. The 2012 Cochrane review reports fewer caesarean births when moxibustion was combined with acupuncture.

Knee osteoarthritis and pain

The overview of knee osteoarthritis reviews, published in 2022, drew on ten systematic reviews that together covered 57 randomized trials with 5,149 participants. Its authors rated all ten reviews as critically low quality on the AMSTAR-2 tool. Of 32 graded outcomes, two were rated high certainty, three moderate, 17 low and 10 very low, largely because of risk of bias.

The pooled total effective rate favored moxibustion (risk ratio 1.17, 95% confidence interval 1.13 to 1.21), but the overview reports obvious publication bias and a small effect size. Several reviews reported pain-score benefits, while GRADE ratings for many pain outcomes were low or very low. The authors conclude that moxibustion appears effective, while noting reduced reliability from high risk of bias in the original studies.

The overview notes that sham moxibustion can still produce false-positive results. Evidence for pain relief is therefore suggestive and of uncertain size, and it should not be generalized to other joints or pain conditions.

Other conditions and side-effect outcomes

A Cochrane review by Zhang and colleagues included 29 randomized trials with 2,569 people with cancer receiving chemotherapy or radiotherapy. Risk of bias was high in 18 studies. Moxibustion plus conventional treatment was associated with better quality-of-life scores and lower nausea and vomiting symptom scores than conventional treatment alone, but the review rated most of these findings as low certainty.

Yuan and colleagues' 2022 review of 21 randomized trials with 1,549 patients studied indirect moxibustion for allergic rhinitis. They reported a statistically significant effect on total effective rate (risk ratio 1.16), with no clear advantage for the visual analog pain score or serum IgE. They rated the total evidence as low quality, and the findings are limited to indirect moxibustion.

Burns, blisters and scarring

Xu and colleagues (2014) reviewed 64 case reports of adverse events from moxibustion, published in 24 articles from six countries. Burns were the most common reported event, with 43 cases in six articles. The review notes that severe burns sometimes left permanent, disfiguring scars and that these were associated with direct moxibustion. Other reported events include allergic reactions, infection, eyelid ectropion, hyperpigmentation and, and, in some case reports, death.

Park and colleagues (2010) reviewed trials, observational studies and 13 case reports. The most frequent events were allergic reactions, burns and infections such as cellulitis and hepatitis C. Their authors state that moxibustion is not entirely free of risk and that the incidence of such events is currently unknown.

Yuan and colleagues report that burns and blisters were the main adverse reactions in their indirect moxibustion trials. The case-report review lists the position of the moxa, its duration, its distance from the skin, practitioner proficiency and the patient's condition among the factors that affect safety.

Smoke, infection and pregnancy

The knee osteoarthritis overview reports that moxa smoke contains mono-aromatic hydrocarbons, formaldehyde and polycyclic aromatic hydrocarbons, and it cites studies that found these at concentrations above standard limits. It notes that high concentrations are toxic to the heart, liver and kidney, while also stating that no clinical reports of related toxic effects were found. Park and colleagues list discomfort from smoke among the trial events they recorded.

Infection is a separate concern. Xu and colleagues describe a case of cellulitis after a person who had no training in East Asian medicine applied direct moxibustion to the skin of the foot. Park and colleagues also describe cellulitis and hepatitis C among reported infections.

Park and colleagues report that pregnant women in the included studies experienced premature birth, premature rupture of membranes and bleeding linked to pressure on the anterior placenta. Xu and colleagues list fetal distress and premature birth among case-report events. Its use in pregnancy should be discussed with a clinician first.

Reporting gaps and limits

The Cochrane review of cancer-treatment side effects found that most included studies did not report related adverse events such as burning or allergic reactions. The knee osteoarthritis overview found that some included reviews reported no adverse events and others did not mention them. The absence of a reported harm in a trial is therefore not evidence that the harm did not occur.

The sources reviewed for this page do not report contamination of moxa products with heavy metals, and they do not address how reduced skin sensation changes the risk of burns. Burns, spreading redness, or fever after treatment are reasons to seek prompt medical assessment, and moxibustion does not replace the assessment or treatment a condition requires.