Excessive sun exposure causes the skin to darken, which can be improved through some medical beauty methods, but it is difficult to achieve "rapid whitening". There are mainly the following methods of medical beauty whitening: - **Whitening injection**: - **Principle**: Its main ingredients, glutathione, tranexamic acid, etc., can inhibit the formation of melanin, promote the metabolic decomposition of melanin, and can also resist oxidation and remove free radicals, thereby achieving the effect of whitening. - **Effect and process**: Generally, injections are given according to the course of treatment. A course of treatment usually consists of 3-10 injections, and injections are given 2-3 times a week. After the injection, the skin tone can gradually brighten, and the whitening effect is more obvious after a course of treatment. - **Precautions**: It is necessary to choose a regular medical institution and a qualified doctor to perform the operation. After treatment, pay attention to sun protection to prevent ultraviolet rays from damaging the skin again and affecting the whitening effect. At the same time, there may be some minor side effects, such as short-term dizziness, nausea, skin redness, etc., which generally resolve on their own. - **Photorejuvenation**: - **Principle**: Use high-energy laser to treat the skin. The laser energy is absorbed by the melanin in the skin, broken into tiny particles, and then metabolized and excreted by the body, thereby reducing the pigmentation in the skin and achieving the purpose of whitening. - **Effect and process**: Generally, multiple treatments are required, with an interval of 3-4 weeks each time. After each treatment, the skin will gradually become fair and even, and a more significant and lasting whitening effect can be seen after about 3-6 treatments. - **Precautions**: Before treatment, you need to tell the doctor in detail about your skin condition and medical history. After treatment, the skin will have slight redness and swelling, which needs cold compresses to relieve. At the same time, you must strictly prevent the sun to avoid skin darkening. Avoid using irritating cosmetics for a short time after treatment. - **Picosecond laser**: - **Principle**: Use a high-energy laser beam to instantly shatter the melanin particles in the skin. It acts more accurately on spots and pigmentation areas than traditional lasers, effectively shatters melanin, and causes less damage to surrounding skin tissue. - **Effect and process**: Usually 1-3 treatments are performed depending on the spots and skin conditions. After each treatment, you can clearly see that the color of the spots has become lighter and the skin has gradually brightened. After multiple treatments, the dull skin tone can be significantly improved and the whitening effect can be achieved. - **Precautions**: After treatment, the skin will have scabs, which need to be allowed to fall off naturally. Do not scratch with your hands to avoid affecting the repair and leaving scars. After treatment, you should also do a good job of sun protection to prevent pigmentation again. After treatment, the skin is more sensitive, so you need to pay attention to skin care and avoid using irritating skin care products.