Gua sha: the clinical use beyond skincare
Gua sha is the press-stroking of lubricated skin with a smooth-edged tool, buffalo horn, jade, or a ceramic soup spoon, along a channel or across a region until sha rises: the red or purple flush of petechiae that marks stagnant Blood and a lodged pathogen drawn out of the surface tissues. It is a clinical procedure of Chinese medicine for wind-cold and wind-heat invasion, for summer-heat and the sha disorders, for stiff and painful neck, shoulders, and back, for cough and a bound chest, and for stagnation of qi and Blood in the channels. The facial gua sha of the beauty industry uses the tool for light lymphatic stroking that raises no sha; it borrows the name and the tool, not the method.
What sha is
Sha is the pathogen and the stagnant Blood lodged between the skin and the flesh, in the cou li, the space of the pores and interstices where the wei qi moves. Wind, cold, damp, and heat enter there; overwork, injury, and long tension leave qi and Blood stagnant there. Scraping presses the stagnant Blood out of the small vessels into the tissue, where the body clears it in a few days, and opens the cou li so that the pathogen leaves with it; fresh Blood and qi follow. Sha rises only where there is stagnation. Healthy tissue reddens under the tool and returns to its colour within minutes. The Qing physician Guo Zhisui's Sha Zhang Yu Heng is the tradition's monograph on the sha disorders, the acute summer collapses with cramping and nausea.
The colour of the sha is read. Light pink that fades within a day is mild and recent. Bright red is heat. Dark red and purple is old stasis, often with heat. Dark and bluish is cold with stasis. Sha that rises only at one point marks the place of obstruction on the channel. The marks fade in two to four days, sooner in a strong person, and the area is not scraped again until they are gone.
Where and how
The skin is oiled with a plain oil or a medicated balm. The tool is held at a shallow angle and drawn in one direction in strokes of a hand's length, with even and moderate pressure, over one line at a time until the sha rises or the skin is warm and red, and then moved to the next line. On the back, the lines run down the Du Mai from GV14 Dazhui below the seventh cervical vertebra and down the two lines of the Bladder channel beside the spine, where the back-shu points of all the organs lie. On the neck, from GB20 Fengchi at the base of the skull down to GB21 Jianjing at the top of the shoulder, and along the shoulders outward. On the chest, lightly, outward along the intercostal spaces. On the limbs, along the channel away from the trunk.
| Condition | Region and channel |
|---|---|
| Early wind-cold, chills, stiff neck | GV14 and the upper Bladder line, BL12 Fengmen and BL13 Feishu; the neck |
| Summer-heat, the sha disorders | Neck, the inner elbows, the back along the Bladder line |
| Neck and shoulder pain, tension headache | GB20 to GB21, BL10 Tianzhu, the upper trapezius |
| Cough, tight chest | Upper back over BL13, the chest lightly |
| Digestive fullness, food stagnation | Mid back over BL20 Pishu and BL21 Weishu |
| Low back pain from cold-damp | BL23 Shenshu and the lumbar Bladder line |
| Bi pain in a limb | Along the affected channel |
Cupping, ba guan, works on the same principle by suction rather than scraping, and the two are often done in one treatment, the cups placed where the sha rose darkest.
Aftercare
The area is kept covered from wind and cold for the rest of the day; warm water is drunk; there is no cold bath, swim, or draught that day, since the cou li are open and a new pathogen enters as easily as the old one left. Rest follows.
When it is never done
Not over broken skin, rashes, sunburn, moles, varicose veins, fractures, or tumours. Not on a person with a bleeding disorder, and not on a person taking warfarin or another anticoagulant, in whom gua sha raises extensive bruising instead of sha. Not on the abdomen or the lower back in pregnancy, and not at all in the first trimester. Not on a person who is severely deficient, very frail, or exhausted by sweating, nor on an empty stomach or straight after a meal, because the release costs qi and a weak person has none to spend. Not with any force on the face, where the skin is thin and the marking would be visible for days. Not as a treatment for a yin-deficient heat pattern, with a red peeled tongue and night sweats, in which there is nothing lodged at the surface to release. Children are scraped lightly and briefly. Once a cold has gone inward, with high fever and a yellow coat, the treatment is herbal, not the scraper.