Clinical Reference / Therapeutic Strategies / Facial Melanosis, Melasma

Facial Melanosis, Melasma


Key Points

  • Facial melanosis (also known as melasma) is a very common condition. In the USA, 5 to 6 million individuals are affected.
  • Melasma usually appears in association with oral contraceptive (OCP) use or pregnancy (“chloasma,” or the “mask of pregnancy”) and is exacerbated by sun exposure.
  • Although the pigmentation usually fades after pregnancy or withdrawal of OCPs, it may persist indefinitely. Melasma may become a chronic condition.
  • Melasma is more common in women than in men, accounting for 90% of cases.
  • Treatment of melasma involves topical drugs, superficial procedures (such as chemical peels), and photoprotection.
  • First-line treatment is a triple combination topical therapy, including hydroquinone, retinoid cream, and corticosteroids. When patients experience irritation to one of the ingredients or a triple combination is unavailable, other compounds with dual ingredients or single agents may be considered as an alternative.

Introduction

Melasma is a chronic condition of hyperpigmented patches that gradually develop on the face, especially on sun-exposed areas, on the forehead, zygomatic cheeks, nose, and upper cutaneous lip. It results from increased epidermal melanin pigment in the epidermis, dermis, or both; increased number of melanocytes or dermal melanophages in the dermis may also result in melasma. It usually appears in association with estrogen exposure in the form of oral contraceptive (OCP) use, hormone replacement therapy (HRT), or pregnancy (“chloasma” or the “mask of pregnancy”). Melasma is exacerbated by sun exposure. Although the pigmentation usually fades after pregnancy or withdrawal of OCPs, it may persist indefinitely; this chronic condition may have a significant psychosocial impact on quality of life.

Initial Evaluation

Clinical images show homogeneously hyperpigmented macules and geographic or irregular patches typically located on forehead, zygomatic cheeks, upper cutaneous lip, and nose. Central facial involvement is most common but mandibular involvement may also occur.

Differential diagnosis

Photoallergic / phototoxic contact dermatitis

Melanosis of Riehl’s (likely a photo-distributed contact dermatitis)

Nevus of Ota, Nevus of Hori (mainly in Asians)

Post-inflammatory hyperpigmentation

Treatment

The therapeutic strategy is to remove the underlying cause (if known), bleach the pigmentation, and prevent the formation of new pigment by reducing and blocking sun exposure.

First-line therapy: First-line treatment is a triple combination topical therapy, including hydroquinone, retinoid cream, and corticosteroids. When patients experience irritation to one of the ingredients or a triple combination formulation is unavailable, other compounds with dual ingredients or single agents may be considered as an alternative. Of the single agents, hydroquinone is the most effective medication option.

  • To eliminate pre-existing pigmentation, apply hydroquinone 4% cream b.i.d. in combination with topical retinoid and corticosteroid creams (such as Tri-luma cream: hydroquinone 4%, tretinoin 0.05%, fluocinolone acetonide 0.01%) only to hyperpigmented areas for 6 to 24 weeks.
  • Strict photoprotection (broad spectrum) is essential adjunctive therapy.

Alternate therapy

Evidence supports that triple-combination cream is significantly more effective at lightening melasma than hydroquinone alone or dual-combination creams, including tretinoin and hydroquinone. However, if patients cannot tolerate the triple combination cream due to irritation, several effective alternative options exist.

  • Adapalene 0.1-0.3% cream q.h.s. (such as adapelene or Differin)
  • Tretinoin 0.025-0.1% cream or gel q.h.s. (such as Atralin, Avita, Refissa, Renova, Retin-A, Retin-A Micro)
  • Azelaic acid 20% cream b.i.d. (such as Azelex) has been shown to be more effective than daily use of 2% (but not 4%) hydroquinone cream

Second line treatment includes peels either alone or in combination with topical medications. Serial glycolic, salicylic, or lactic acid peels may be an effective adjunctive therapy, especially in combination with adapalene and azelaic acid creams. A cautious approach should be taken, as high-potency chemical peels can induce increased hyperpigmentation through irritation of the skin with subsequent post-inflammatory hyperpigmentation.

Laser targeting cutaneous pigment may be used in cases that fail medical topical therapy.

Pitfalls

  • Strict photoprotection, including avoidance of UVA light, UVB, and visible light, is an essential aspect of melasma treatment. A broad-spectrum sunscreen should be used daily in combination with hats and sun avoidance. See handout Choosing a Sunscreen.
  • Hydroquinone may also lighten normal skin; it should be applied only to affected areas.
  • After treatment, melasma will recur if sun exposure is not kept to a minimum; ongoing photoprotection is critical to maintain satisfactory treatment.
  • Both hydroquinone- and topical retinoid-containing products can be irritating and even sensitizing. Inclusion of a low-potency topical steroid can minimize the irritancy but not the possibility of sensitization.
  • Hydroquinone may result in the cutaneous ochronosis (deposition of phenol compounds, such as hydroquinone, in the dermis) at the site of application, causing hyperpigmentation. This may be confused with failure of the treatment regimen, and risk factors to develop ochronosis include increased potency of topical medications and prolonged use. Although rare, it can result in irreversible pigment changes and hardening of the skin.

When to refer to a dermatologist

  • When the diagnosis of melasma is not clear.
  • If treatment and photoprotection is not resulting in fading of pigment or if the pigment is darkening.
  • For evaluation for chemical peels, laser, or other adjunctive therapies.
  • If a diagnosis of cutaneous ochronosis is suspected as a complication of hydroquinone therapy.

Clinical Case

  • 32-year-old healthy woman
  • Six months’ history of progressively darkening skin on the forehead, lateral cheeks, nose
  • Does not wear daily sunscreen
  • Exercises several times a week outdoors without sunscreen
  • Started taking estrogen-containing birth control pill in the past year

Initial evaluation

  • Geographic patches of hyperpigmentation
  • The diagnosis of moderate melasma is discussed; recommend referral back to gynecologist to discuss alternative contraceptive options
  • Prescription for triple combination cream is given: hydroquinone 4% / tretinoin 0.05% / fluocinolone 0.01% to be applied once daily in the evening
  • Extensive counseling on photoprotection; patient handout given
  • Follow-up evaluation in 2 months

Two-month follow-up

  • Pigmentation is improved but not fully resolved; patient is tolerating the prescribed cream without any complications and uses it daily; patient endorses strict photoprotection
  • Continue use of triple combination cream
  • Follow-up evaluation in 3 months (pigmentation resolved)

References

Rajartnam R, Halpern J, Salim A, Emmett C (2010). Interventions for melasma, Cochrane Database of Systematic Reviews, 7: ArtCD003583.

Pandya AG et al (2011). Reliability assessment and validation of the Melasma Area and Severity Index (MASI) and a new modified MASI scoring method, JAAD, 64: 78-83.

Ortonne JP (2006). Retinoid therapy of pigmentary disorders, Derm Therapy, 19: 280-288.

Rendon et al (2006). Treatment of melasma, JAAD, 54: S272-81.