Rash is a kind of red or purple spots and patches that we can see under the skin. In fact, what oozes from blood vessels is blood, which contains metabolites. Rheumatism in the body and some metabolites in the blood cause blood circulation disorder, which will lead to rash.

Scraping scab and congestion are not the same thing: congestion is mostly caused by trauma, with a large amount of bleeding, pain in the congestion area and inconvenient movement. There are few red or purple spots bleeding after scraping, which are oozing from capillaries. The pain disappears after scraping, and the discharge of scraping promotes blood circulation and accelerates metabolism, which has therapeutic effect.

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