The injection of hydration injection can play an improvement role on the aging cells in the skin, not only can smooth out the fine lines on the face, but also can whiten the appearance, make the skin look hydrated and transparent, and maintain a youthful appearance, but there are certain side effects. The main component of hydration injection is hyaluronic acid, which is not maintained in the body for a long time, and will be metabolized completely by the body in about six months, so it needs to be injected continuously. Multiple injections may produce the following side effects: 1, the needle will stimulate damage to the epidermis, destroy the skin self-protection barrier, but also trigger a subtle traumatic inflammation, improper care will cause skin needle infection; 2, hydrating needle injection will stimulate the body rejection reaction, so that the skin edema, rash, puffiness and bruising; 3, hydrating needle will be difficult to absorb the normal skin beauty ingredients directly into the dermis, the skin Stimulation is difficult to completely avoid, can impede the normal metabolism of the skin, resulting in pseudo-skin sensitivity; 4, hydrophobic needle ingredients impure, complex, the amount of subcutaneous capillary rupture will cause the redness of the capillaries aggravated, local stiffness, lumps, etc.. Therefore, it is recommended that seekers should choose a professional hospital and experienced doctors to minimize side effects.