I. Treatment and prevention
As can be seen from the above picture, there is a melanocyte in the epidermis, which becomes an irregular pigment group under the stimulation of sunlight and spreads to the deep skin. Sun exposure has a certain relationship with the onset or aggravation of chloasma, so we should pay attention to sun protection; When going out, you can apply a cream containing sunscreen ingredients (such as 5% titanium dioxide cream and 5% salicylic acid benzoic acid ointment) or hold a parasol.
In addition, according to the complex causes of chloasma, in order to avoid chloasma, we should control our emotions, pay attention to rest and avoid staying up late. Patients with chronic hepatitis, cirrhosis and other diseases should actively treat the primary disease; Stop taking oral contraceptives, phenytoin sodium and other drugs. Choosing correct and high-quality freckle-removing skin care products and taking vitamin C and vitamin E orally can inhibit the formation of melanin. Keeping a proper amount of exercise can make the skin more ruddy and shiny and enhance resistance.
Second, drugs for external use
Before the popularization of optical equipment such as laser, topical medicine was the main method to treat chloasma. The cycle is longer, and different people have different therapeutic effects.
1) hydroquinone cream: Hydroquinone is an inhibitor of tyrosine-tyrosinase system, which can inhibit the formation of melanosome and accelerate the decomposition of melanosome. Daily use of 3% concentration preparation, the general effective time is about 3 months, need to explain to patients. However, if the ratio is not used properly, there may be adverse reactions, such as irritating contact dermatitis, permanent skin leukoplakia, exogenous brown and nail bleaching, nail brown lesions and so on.
2) Tretinoin cream: It can reduce pigmentation, but the main problem is that it takes about half a year to take effect slowly. Generally speaking, the concentration gradually increases from low concentration. Starting from 0.05%, it increased to 0. 1% after1month, and gradually decreased to 0.05% after the effect was obvious. Stop using it after satisfactory results are obtained.
3) azelaic acid 15% ~ 20% cream is commonly used in clinic. Twice a day, the course of treatment is about 6 months. 1% ~ 5% patients may have itching, burning sensation, tingling, numbness,
4) chemical peeling of fruit acid: fruit acid is an effective auxiliary method to treat chloasma, and its concentration is
5) Others: L- vitamin C, arbutin, glutathione, lignin peroxidase, tranexamic acid, etc. External use can inhibit epidermal melanin synthesis and can be used as external preparation.
Third, optical instrument therapy
Because chloasma is characterized by abnormal melanocyte activity in pathophysiology, laser or intense pulsed light should minimize the stimulation to melanocytes in the treatment of chloasma to avoid the aggravation of chloasma. Therefore, in terms of energy selection, only the melanocyte particles inside or between melanocytes are selectively photoexploded, while the function of melanocytes is inactivated or inhibited by low energy and multiple photoexplosions. At the same time, multiple light-generating cells of melanocytes can make melanocytes smaller, which is more conducive to being swallowed and excreted.
1. Low-energy Q- FM ruby laser and Q- FM Nd: YAG laser (eggshell muscle laser, black-faced doll and white porcelain doll) can be used to treat chloasma. The former has a better effect on removing dermal melanosome, and can also be treated with intense pulsed light (photon rejuvenation), pulsed carbon dioxide laser and Q- FM emerald laser. The new laser picosecond 755nm laser also has a good effect on chloasma, but it is difficult to market at present because of its high price.
2. Intense pulsed light: Although intense pulsed light has a certain curative effect on chloasma, it also has the risk of aggravating pigmentation after treatment, especially for people with darker skin. Intense pulsed light can not only improve epidermal pigment, but also correct skin vascular abnormalities and inflammation, which is also beneficial to the treatment of chloasma.
Long spots are melanin deposits caused by the obstruction of skin meridians. If you want to remove freckles, you must first clear the skin meridians and let melanin be excreted through normal metabolism. At present, the conventional method only removes melanin from the surface, thus treating the symptoms rather than the root cause.
References:
Baidu encyclopedia chloasma butterfly spot