Chloasma, also known as melasma or liver spots, is a type of facial hyperpigmentation characterized by brownish patches on the face.

bubble_chart Etiology

The cause of the disease is unclear and is often thought to be related to changes in endocrine function. It is seen in women during pregnancy or those taking oral contraceptives, as well as other factors. The chloasma (Chloasma gravidarum, pregnancy-related chloasma) in pregnant women begins between the 3rd to 5th month of pregnancy and gradually fades after childbirth. Facial pigmentation may be due to the combined effects of estrogen and progesterone, which stimulate melanocytes, while progesterone promotes the transport and diffusion of melanosomes, increasing melanin production and leading to pigmentation.

It is also seen in chronic gastrointestinal diseases, liver diseases, subcutaneous nodules, cancerous tumors, cervical malignancy with cachexia, and chronic alcoholism. Long-term use of certain medications such as phenytoin sodium, chlorpromazine, and contraceptives can also cause chloasma. Additionally, intense sun exposure and the use of cosmetics can induce chloasma. Chloasma is also observed in unmarried, non-pregnant women or men for unknown reasons.

bubble_chart Pathological Changes

Hyperpigmentation in the epidermis, with abundant pigment in melanophages in the dermis. Slight lymphocyte infiltration is observed around dermal blood vessels and hair follicles.

bubble_chart Clinical Manifestations

The skin lesions are light brown or yellowish-brown patches with relatively clear boundaries and irregular shapes. They are symmetrically distributed around the orbits, forehead, eyebrow arches, nose, both cheeks, lips, and perioral areas, without any subjective symptoms or systemic discomfort.

Avoid exposure to sunlight, and try to eliminate the disease cause if there is one. For melasma caused by contraceptives, discontinue their use, though the condition may not fade immediately.

1. Systemic Treatment: Administer high doses of vitamin C orally, 1–3g daily, or 2g intravenously. Vitamin C reduces darker oxidized pigments to lighter reduced forms and converts dopaquinone back to dopa, thereby inhibiting melanin formation.

2. Topical Treatment: Combining topical and oral medications yields better results.

(1) Depigmenting Agents

1) Hydroquinone Preparations: 3–5% hydroquinone cream, 2.6% tert-butylphenol cream, 10–20% monobenzyl ether of hydroquinone cream, and 3% hydroquinone monopropionate are effective. Hydroquinone blocks the tyrosine-to-dopa reaction catalyzed by tyrosinase, reducing melanin formation by preventing tyrosine oxidation into dihydroxyphenylalanine (DOPA). Avoid applying hydroquinone cream to unaffected skin or overusing it to prevent uneven pigmentation. Rarely, it may cause allergic dermatitis. A 20% monobenzyl ether of hydroquinone emulsion or ointment can be used, converting to hydroquinone in the skin for similar effects, though it may cause allergies or permanent depigmentation in stubborn cases.

2) Retinoic Acid Preparations: A mixture of 0.1% retinoic acid, 5% hydroquinone, and 0.1% dexamethasone in a hydrophilic ointment or equal parts propylene glycol and alcohol solution (must be freshly prepared). Apply twice daily; initial erythema and irritation may occur, but significant pigment reduction is seen after 4–6 weeks.

3) 2–5% hydrogen peroxide can also be used for depigmentation.

1) Para-Aminobenzoic Acid (PABA): Absorbs UVB (280–320nm). A 5% PABA in 50–60% alcohol solution is most effective but may cause allergies. Now clinically used.

2) Phenyl Salicylate (Salol): Often formulated as a 10% cream.

3) Titanium Dioxide: 5% titanium dioxide cream protects against sunspots.

(3) Anti-Aging Agents

1) 1% Vitamin E Cream: Inhibits free radical-induced lipid peroxidation, preventing skin aging and pigmentation.

2) 15% Seabuckthorn Fruit Emulsion: A blend of vegetable oil extracted from Seabuckthorn Fruit and emulsion base. Rich in vitamins C, E, β-carotene, and amino acids, it combats aging and reduces pigmentation.

3. Chinese Medicine Treatment: Various Chinese medicinals are used with varying efficacy. Treatment should be tailored to the patient’s pattern: for liver depression qi stagnation, use liver-soothing and qi-regulating methods with formulas like Xiaoyao San or Bupleurum Liver-Soothing Powder. For spleen deficiency, modify Two Old Ingredients Decoction or Four Gentlemen Decoction. For kidney deficiency, adjust Six-Ingredient Rehmannia Pill.

Many melasma patients have kidney yin deficiency and can be treated with Lycium and Rehmannia Decoction plus Phelloendron Bark and Dried Tangerine Peel. For blood stasis and liver qi stagnation, use Blood Mansion Stasis-Expelling Decoction or Peach Kernel Four Ingredients Decoction.