Melasma

Overview

This Guidelines summary covers information from the Primary Care Dermatology Society (PCDS) guidance on the management and treatment of melasma (also called chloasma), including links to further resources.

Reflecting on your Learnings

Reflection is important for continuous learning and development, and a critical part of the revalidation process for UK healthcare professionals. Click here to access the Guidelines Reflection Record.

Features and Aetiology

Features

• Melasma is the most common cause of facial hyperpigmentation and is characterised by symmetrical, blotchy, brownish pigmentation that becomes more pronounced after sun exposure.

Aetiology

• The pigmentation is caused by the overproduction of melanin, which is taken up by the keratinocytes (epidermal melanosis) and/or deposited in the dermis (dermal melanosis)
• The exact cause is unknown
• There is a genetic predisposition, with at least one-third of patients reporting other family members to be affected
• The most important exacerbating factor is ultraviolet (UV) radiation. Other factors include pregnancy and hormonal contraceptives
  • in the context of pregnancy, melasma is regarded as a normal physiological change, along with darkening of the nipples and linea nigra
• The rarity of melasma in postmenopausal women on oestrogen-containing hormone replacement therapy and the fact that men are occasionally affected suggests that oestrogen alone is not the causative agent.

History

• Melasma predominantly affects skin types III and IV, particularly those of Latin-American and Middle-Eastern or Asian descent
• Ninety percent of melasma cases are reported in female patients
• Melasma most commonly arises in the third and fourth decades of life.

Clinical Findings

Distribution

• Bilateral and frequently symmetrical involvement, most commonly centrofacial (forehead, cheeks, nose, upper lips), but can affect the lateral cheek or jawline. The forearms can also be affected.

Morphology

• Macules and patches
• Wood's lamp examination can be helpful to identify the depth of the melanin pigmentation and determine the type of melasma (epidermal, dermal, or mixed)
  • epidermal melasma normally appears brown (usually light brown in skin types 1 and 2) and shows enhanced colour contrast with Wood's lamp examination
  • dermal melasma often appears slightly grey or bluish on gross examination and shows less colour contrast with Wood's lamp
  • categorisation of the type of melasma is useful because it may help guide treatment options and patient expectations; dermal melasma is generally less responsive to therapy, especially to topical modalities.

Differential Diagnosis

• There are many other causes of hyperpigmentation affecting the face and neck, which include those outlined in Box 1. This information is taken from the PCDS topic page on hyperpigmentation of the face and neck.

Management

General Advice

• Although epidermal melasma is more likely to respond to topical therapies than dermal melasma, explain that all types of melasma can be difficult to treat, and recurrence in subsequent years is common
• Avoid/reduce the use of scented deodorant soaps, toiletries, and cosmetics, as these may cause a phototoxic reaction that exacerbates matters
• Provide a patient information leaflet such as this example from the British Association of Dermatologists: bad.org.uk/pils/melasma.

Year-round Ultraviolet Light Protection

• Year-round UV light protection is the most important aspect of treatment
• Advise patients to take advantage of shade and wear a broad-brimmed hat for UV light protection
• Make patients aware that light coming through glass and from electronic devices will also worsen melasma
• Sunscreen:
  • advise patients to use a mineral sunscreen, which protects against UVA, UVB, and visible light
  • sunscreen built into cosmetics will not suffice as protection
  • advise patients to use a sunscreen with sun protection factor of 30 or more and with a four- or five-star UVA rating
• advise patients to use a teaspoon amount to the head and neck, several times per day
• vitamin D supplements may be required.

Hormonal Contraceptives

• Progesterone-only contraceptives are more commonly associated with melasma than any other type of hormonal contraception; however, changing to an alternative should only be considered if symptoms started/became significantly worse after a hormonal contraceptive was commenced
• After stopping/changing contraception, any improvements are likely to take a considerable amount of time.

Table 1: Treatment of Melasma in Primary Care

Table 2: Specialist Treatments for Melasma

Referral to Camouflage Department

• Camouflage teams tend to be based in hospital outpatient departments. If this is not the case, contact your local dermatology department or Changing Faces: changingfaces.org.uk.
• Patients may wish to camouflage with ‘fake tan’ products.