Why does the left hand itch?

& lt& lt Huangdi Neijing; It is said that all pain and pain belong to the heart.

There are two kinds of itching:

First, the general principle is itchy, the meridians are blocked, and the righteousness is over, but it will not pass.

Justice drives away evil in appearance, but its power is not enough. Some allergic skin diseases such as urticaria are common.

Second, it itches if you are not proud.

This is a symptom of insufficient vaginal fluid and cannot moisturize the skin. Psoriasis and so on should belong to this category.

Dermatosis: those who are partial to the impassability help their yang, and those who are insufficient in yin, give consideration to their yin and make it harmonious, so there is no disease.

What other symptoms are there?