الفهرس 
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Abstract
Facial hyperpigmentation is the most cosmetically important complaint. It is common in middle-aged women, and is related to endogenous (hormones) and exogenous factors (such as use of cosmetics and perfumes, and exposure to sun radiation). It is important to understand melanogenesis and factors affecting it [e.g. UVR, drugs and chemicals, hormonal factors, inflammation (post inflammatory hyperpigmentation), inhibitors of melanogenesis] and this will help in recognizing the mechanism by which hyperpigmentation can occur in different diseases. Melasma (chloasma) and PIH are the most common causes of facial hyperpigmentation, but there are many other causes such as SL, freckles, drugs, Riehl’s melanosis, poikiloderma of Civatte and erythromelanosis follicularis faciei that lead to facial hyperpigmentation. Treatment of facial hyperpigmentation to achieve satisfactory results is very important as this clinical aspect may cause psychological and emotional stress and can pose a negative impact on a person’s health-related quality of life. Photoprotection is one of the most effective steps in facial hyperpigmentation treatment and should be initiated early and throughout the treatment process. The current treatment of facial hyperpigmentation include multiple modalities such as topical application of agents interfering with melanogenesis, systemic agents improving hyperpigmentation, mesotherapy, resurfacing procedures (Chemical peeling, Dermabrasion and IPL) and Laser. A variety of topical agents are available to treat hyperpigmentation. These topical agents can interfere with the pigmentation process at several different levels of melanin proudcution. Hydroquinone has long been a mainstay for the topical treatment of hyperpigmentation. However, concerns regarding ochronosis, allergic and irritant contact dermatitis, melanocyte toxicity, difficulty formulating stable preparations, and carcinogenicity have prompted a search to find alternative agents. Other agents that have already been used topically to treat hyperpigmentation include azelaic acid, arbutin, retinoic acid and kojic acid. Newer topical agents that havebeen shown to have partial or total efficacy in treating hyperpigmentationinclude soy, licorice, , mequinol, rucinol, , niacinamide, ellagic acid, dioic acid, and N-acetyl glucosamine. There are new systemic agents that may be effective in treating facial hyperpigmentation. These agents include glutathione, procyanidins and tranexamic acid. Many substances have been used in mesotherapy for whitening. These chemicals act as antioxidants and are claimed to decrease pigmentation, such as glutathione, ascorbic acid , glycolic acid or pyruvate. Multiple substances are used in Chemical peeling for treating facial hyperpigmentation. These substances include glycolic acid, TCA, salicylic acid and tretinoin. Proper patient selection, skin priming and post peel care are important to achieve satisfactory outcome and reduce post peel complication. It can be combined with other treatment modalities (e.g. topical bleaching agents, laser) for best results. Dermabrasion has been reported as a possible alternative treatment for recalcitrant melasma. The prevalence of its adverse reactions, especially PIH, may be why dermabrasion has been studied as a possible therapy for melasma but is not a standard treatment modality. Intense Pulsed Light (IPL) is a nonlaser light source which is safe and effective for treating refractory melasma. Furthermore, IPL can be used as an adjuvant to topical therapy to speed improvement of lesions and this may subsequently improve patient compliance. Laser has been used with variable success for the treatment of hyperpigmentation. The use of lasers for the treatment of pigmentary disorders is based on the theory of selective photothermolysis. For more refractory hyperpigmentation disorders, ablative lasers (pulsed/scanned carbon dioxide or erbium:YAG laser) were reported to ablate superficial portions of the skin, including abnormal melanocytes. There are many types of laser used in this concern (e.g. Q-Switched Ruby laser, Q-Switched Alexandrite laser, Q-Switched Nd:YAG and Fractional Photothermolysis). Laser should be considered third-line treatments in severe refractory patients who have not respond to topical preparations or chemical peels In conclusion, melasma and PIH are the most common causes of facial hyperpigmentation which have major negative impacts on quality of life. There are several effective treatment modalities, including topical bleaching agents, chemical peeling and laser that can improve these disorders. Additionally, UV protective measures, such as the use of sun screens, sun- protective clothing and sun avoidance, are fundamental to the successful management of these conditions.