Melasma is a common pigment disorder that causes brown or gray spots to appear on the skin, especially in the facial area. The most common areas for appearance of the cost on the face include: nasal bridge, front, head, cheeks, upper lip. Costs may also appear in other parts of the body, especially those exposed to many sun rays such as forearms, neck, and shoulders. Women are more likely to be affected than men. Studies show that only 10 percent of all cases of menopause occur in men. Dark-skinned women and pregnant women are more likely to develop edema. The exact cause of the malignancy is not known, but it is likely to occur due to malignant melanocytic cells, which cause the skin to produce its natural color, causing excessive pigmentation. The stimuli include: hormonal changes during pregnancyOr hormonal therapy or taking birth control pills, exposure to the sun, the use of some skin care products that cause skin irritation. It should be said that the costs may be genetically as people with relatives with the cost of the most vulnerable to the incidence of cost. 
The cost can be prevented by avoiding direct sun exposure by wearing hats and using a sun shield with a minimum protection factor (SPF) of 50, containing physical blockers such as zinc oxide, And titanium dioxide to prevent ultraviolet rays, and not to rely on sunscreens that contain chemical blockers only because they do not prevent UV rays of type A and B sufficiently. To enhance the effectiveness of cures and reduce the development of MS D of the spots. 
Treatment of costs
It can disappear costs resulting from pregnancy or the use of contraceptive pill automatically after birth or stop using the contraceptive pill. However, costs may persist for several years or for some people. In cases where the cost does not disappear on its own, the costs can be treated in many ways . It is worth noting that the treatment of costs under the care of a dermatologist may take a few months to see the improvement, since the cost may be stubborn and does not disappear easily . It should also be noted that treatment may continue for a period after elimination of the cost to prevent recurrence of the cost again. To ensure that the treatment does not fail, people should reduce exposure to sunlight. Pregnant women or nursing mothers should not treat costs without consulting a doctor because of the potential risks of drugs to fetal and neonatal development. Methods include treatment of costsInclude:  
Hydroquinone:Hydroquinone Hydroquinone is the first treatment to eliminate the cost. And comes in several forms of pharmaceutical, including: cream, lotion, and gel. This medicine is applied topically to the skin to lighten the skin. With concentrations as low as 2% and concentrations as high as 4%. The higher concentration is associated with a greater risk of skin irritation than the lower concentration. Hydroquinone should be applied to lipid spots twice a day with the need to place a sunscreen above the hydroquinone in the morning. Possible side effects of celiac treatments include temporary skin irritation. People who use hydroquinone therapy at very high concentrations and for long periods ranging from several months to years are at risk of a side effect called exogenous exfoliation (English:
Tretinoin and corticosteroids: These drugs help to increase the effectiveness of skin lightening treatments, for example: retinoic acid (0.025-0.1%), Tazarotene (0.05-0.1%) and adapalene 0.1-0.3%
Other topical medications: The dermatologist may prescribe azelaic acid at 15-20%, Kojic acid, 12% lactic acid laxation, and glycolic acid creams at the concentration 10-20%, and peeled glycolic acid with high concentrations to help reduce the cost.
If the drugs listed above do not cure the cost, the doctor may resort to other methods of treatment. It should be said that there is no guarantee that these measures will be effective in eliminating the costs, or reduce the resulting stains, and should be said that severe treatments or abrasive treatments can cause the emergence of the cost or increase symptoms. Other treatments include the cost of many procedures such as chemical peels, or skin abrasion or laser therapy, and in the following statement of these procedures : 
Chemical peels: (English: Chemical peel), the treatment costs of chemical peeling under the supervision of a physician through the use of chemicals such as acid peeling Glicolak concentrations ranging from 30-70%, or through the use of different combinations , such as: the combination of 10% of the acid Glycolic acid and 2% hydroquinone.
Surface peeling : Microdermabrasion, during which the skin is peeled and regenerated using soft crystals such as soft diamond flakes or aluminum oxide crystals as well as a vacuum pipette pump. Treatment takes several sessions, lasting from a few minutes to one hour. It should be noted that the injured should also use sunscreen and other creams to get the best results.
Laser therapy: can be used as a laser to treat the costs , but the results are temporary in the habit, where studies have shown that the laser does not reduce hyper – pigmentation of the skin as it may increase the symptoms of some types of costs, so should consult a doctor before using the laser treatment for cost. The use of lasers to treat the costs may require several sessions before seeing the expected results.
↑ “What is melasma” , www.medicalnewstoday.com , Retrieved 10-1-2019. Edited.
^ A b t “Melasma” , Www.medicinenet.com , Retrieved 10-1-2019. Edited.
↑ “MELASMA: DIAGNOSIS AND TREATMENT” , www.aad.org , Retrieved 10-1-2019. Edited.