Melasma (Dark Skin Pigmentation)
Interesting Facts About Melasma
- This common skin disorder has no medical consequences. Melasma is a completely benign skin disorder with no negative health consequences.
- Melasma mostly occurs in women. Men are affected in 10% of cases.
- Dark-skinned races (Hispanic, Middle Eastern, Asian, and Indian descent) tend to have more pronounced melasma than others. People with light skin have less active pigment-producing cells (melanocytes).
- There is no cure for melasma.
Melasma (also known as chloasma or the mask of pregnancy), the Greek term for “a brown spot", is a dark facial skin discoloration. Melasma is a very common skin disorder and typically occurs on sun-exposed areas of the face.
Melasma doesn't cause any other symptoms besides skin discoloration but may be of great cosmetic concern.
Melasma is characterized by symmetrically distributed patches with irregular borders ranging from light brown to dark brown to gray-brown. The pigmentation usually appears on the cheeks, lips, nose and forehead. Rarely the skin discoloration can also occur on the upper arms and other sun-exposed locations.
The precise cause of melasma remains unknown. It is believed to be due to an increase in the production of melanin, the pigment responsible for the dark color of the skin. The possible mechanism is stimulation of pigment-producing cells (melanocytes) by the female sex hormones (estrogen and progesterone) to produce more melanin when the skin is exposed to sun.
Melasma triggers and risk factors include:
- Heredity. People with a family history of melasma are more likely to develop it[4]. More than 30% of people with melasma have a family history of this skin disorder.
- Female hormones estrogen and progesterone. Melasma is often associated with the female hormones estrogen and progesterone. It is especially common in pregnant women. Melasma also occurs as a side-effect of taking oral contraceptives (birth control pills) and injected depot contraceptive preparations. The incidence of oral contraceptive-induced melasma has been reported to range from 10% to 30%. Progesterone seems to play a critical role in the development of melasma.
- Sun exposure is the biggest culprit[4]. Ultraviolet light from the sun, and even very strong light from light bulbs, can stimulate pigment-producing cells, or melanocytes in the skin. Melasma is more pronounced during the summer months as a result of sun exposure.
- Thyroid dysfunction. Thyroid dysfunction[3] may also lead to development of melasma.
- Race. Women with a light brown skin type who are living in regions with intense sun exposure are particularly susceptible to developing this condition.
- Certain medications. Phototoxic and photoallergic medications (e.g. tetracyclines, anti malarial drugs, antiepileptic medications) have been reported to cause melasma in rare cases.
Medications that may cause melasma as a side effect:
| Drug | Incidence |
|---|---|
| Activella Tablets | |
| Alesse-28 Tablets | |
| Aygestin Tablets | |
| Climara Pro Transdermal System | |
| Climara Transdermal System | |
| Depo-Provera Contraceptive Injection | Less than 1% |
| Estratest | |
| Levlen | |
| Levlite 28 Tablets | |
| Lo/Ovral-28 Tablets | |
| Menostar Transdermal System | |
| Ortho Cyclen/Ortho Tri-Cyclen | |
| Ortho Evra Transdermal System | |
| Ortho Tri-Cyclen Lo Tablets | |
| Ortho-Cept Tablets | |
| Ovral-28 Tablets | |
| Ovrette Tablets | |
| Premarin Intravenous | |
| Premarin Vaginal Cream | |
| Premphase Tablets | |
| Prempro Tablets | |
| Prometrium Capsules (100 mg, 200 mg) | |
| Seasonale Tablets | |
| Topamax Sprinkle Capsules | Rare |
| Topamax Tablets | Rare |
| Tri-Levlen | |
| Triphasil-28 Tablets | |
| Vivelle Transdermal System | |
| Vivelle-Dot Transdermal System |
Melasma, possibly persistent
| Drug | Incidence |
|---|---|
| Estrasorb Topical Emulsion | |
| EstroGel 0.06% | |
| Femtrace Tablets | |
| Lunelle Monthly Injection | |
| Premarin Tablets | |
| Premphase Tablets | |
| Prempro Tablets | |
| Yasmin 28 Tablets |
Although the condition is benign, because of its dermal component and tendency to relapse, melasma is often difficult to treat. The mainstay of treatment remains topical depigmenting agents.
- Depigmenting agents
- Hydroquinone. Hydroquinone cream (2% or 4%) is most commonly used. It can help fade existing melasma spots. Hydroquinone inhibits tyrosinase (enzyme that catalyzes the production of melanin), leading to the decreased production of melanin.
- Tretinoin cream. The response from tretinoin cream can be slow, with improvement taking 6 months or longer. The retinoid is believed to work by increasing keratinocyte turnover and thus limiting the transfer of melanosomes to keratinocytes. The major adverse effect is skin irritation, especially when the more effective, higher concentrations are used. Temporary photosensitivity and paradoxical hyperpigmentation can also occur.
- Azelaic acid. Azelaic acid, available as a 20% cream-based formulation, appears to be as effective as 4% Hydroquinone and superior to 2% HQ in the treatment of melasma. The mechanism of action is not fully understood. Unlike HQ, azelaic acid seems to target only hyperactive melanocytes and thus will not lighten skin with normally functioning melanocytes. The primary adverse effect is skin irritation. This agent is not associated with phototoxic or photoallergic reactions.
- Kojic acid. Attempts with kojic acid demonstrated no more efficacy than other therapies, but more irritation.
- Combination therapy. Combination therapy offers the best results. The mixture of tretinoin 0.1%, hydroquinone 5%, and dexamethasone 0.1% (Kligman's formula) demonstrated better results than any of the medications alone.
- Mild cortisone
- Chemical peels (exfoliative agents). Chemical peels exfoliate the outer layer of skin. The most common include alpha-hydroxy acid, trichloroacetic acid, glycolic acid, lactic acid and various fruit extracts. The effectiveness of many of the lighter strength peeling agents is poor. The stronger peeling agents do the work but they also carry the risk of side effects such as burning, skin peeling, scarring and even worsening the skin discoloration
- Laser rejuvenation. In severe cases, laser treatments can be used to remove the dark pigment.
- Microdermabrasion
- Sun protection It is very important to minimise sun exposure on the face. Use a broad-spectrum very high protection factor sunscreen of reflectant type and apply it to the whole face. Alternatively, use a make-up with a sunscreen in it.
References and Sources:
- 1. Melasma. American Academy of Dermatology
- 2. Melasma : Article by Andrew D Montemarano. eMedicine
- 3. Lutfi RJ, Fridmanis M, Misiunas AL, Pafume O, Gonzalez EA, Villemur JA, Mazzini MA, Niepomniszcze H. Abstract Association of melasma with thyroid autoimmunity and other thyroidal abnormalities and their relationship to the origin of the melasma. J Clin Endocrinol Metab. 1985 Jul;61(1):28-31. PubMed
- 4. Grimes PE. Abstract Melasma. Etiologic and therapeutic considerations. Arch Dermatol. 1995 Dec;131(12):1453-7. Review. PubMed
- 5. Patricia T. Ting and Benjamin Barankin. Brown macules on the cheeks. Can Fam Physician. 2005 March 10; 51(3): 353–355. PubMedCentral