Brief Answer:
Melasma; sun protection and pigment reducing creams; chemical peels

Detailed Answer:
Hello. Thank you for writing to us

I have gone through your query and I have also reviewed the Images.

I can see that she has brownish patches of pigmentation on both cheeks as well as a linear band of pigmentation just above the right eyebrow.
This is commonly known as Melasma.
Melasma affects sun-exposed skin of face, commonly malar area/ cheeks, dorsum of nose, forehead (area above eyebrows), upper lip and sometimes other sun exposed sites like forearms as well.
It is idiopathic in most cases i.e there is no known cause.

Treatment of melasma consists of 2 essential components i.e sun protection and pigment reducing cream/ agents.

Sun protection should be strict and for that purpose I usually advice a broad spectrum sunscreen (spf 50 or more) in my patients of melasma.
Sunscreen should be applied throughout the day. It should be reapplied every 2-3 hours( i.e 8 AM, 11 AM and 2 PM).

In addition to sunscreens, pigment reducing agents would help lighten the patches.
Pigment reducing agents work either by inhibiting the synthesis of new melanin Or by exfoliating already existing pigment/ melanin.

These creams are formulated with one or more of the various pigment reducing active ingredients like kojic acid, hydroquinone, tretinoin, fluocinolone acetonide, glycolic acid, azaleic acid, arbutin, licorice etc. Various creams are available on prescription of a dermatologist.

These pigment reducing formulations are to be used once daily at night.

In addition to sunscreen and pigment reducing creams, she may also take a few sessions of chemical peeling from a dermatologist.
Glycolic acid chemical peel is particularly beneficial for melasma. A session is usually perfomed once every 2-3 weeks.

I suggest that she visits a dermatologist in vicinity for more details and for the needful.

Regards

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