The technique is painless, but it is definitely not pretty.
When performing gua sha, the therapist uses a smooth-edged tool to repeatedly stroke the skin. Gua means “to rub” or “press stroke”. Sha is a term that describes the blood congestion in surface tissue in areas where the patient may experience stiffness and pain; sha is also the term for the little red dots that are raised from applying gua sha.
The discoloration caused by gua sha is not a bruise. Bruising occurs when a blow or shear force damages capillaries and causes bleeding into the tissue. In contrast, during gua sha, blood cells are extravasated (or pressed) through the capillary walls without damage to the capillaries or the surrounding tissues. The area that is treated often feels a bit tender following gua sha (similar to a mild sunburn) but the overall result is immediate relief of pain and improvement in range of motion.
The petechiae caused by gua sha range in color from fresh red to dark red, blue, or nearly black. When gua sha is applied at the site of a new or relatively acute problem, the petechiae are usually bright red. This is because the blood stuck in the connective tissue under the skin has not been there for long. In contrast, the petechiae that result when gua sha is applied to an area of chronic pain or injury are often bluish or even black. This is because the blood has been stagnant for an extended period.
You can see in the photos below that the petechiae on my neck and shoulders have a bluish cast to them. This is because, although the crick that I had in my neck had only been bothering me for a couple of weeks, my neck has been subject to problems ever since a car accident which occurred over 12 years ago. The color of the petechiae tell me that my current pain is an acute flare up of a chronic problem.
How quickly the petechiae fade following gua sha is also significant. In young people with healthy, vital circulatory systems, petechiae fade very quickly. If I perform gua sha on my children in the morning, the petechiae are often nearly gone by the end of the day. In contrast, in older individuals, individuals with sluggish circulation, or in cases of long-standing pain, the petechiae may take nearly a week to fade completely.
In the series of photos below, you can see that by 48 hours after the initial treatment, the appearance of my skin was nearly normal. Under bright lights or close inspection, it was still possible to see some discoloration, but I felt no need to wear a scarf to cover it. If patients are planning a special occasion that involves clothing that will expose the area to be treated, however, I encourage them to allow at least a week for the sha to fade completely.