Melasma vs Hyperpigmentation vs Sun Spots: Notes Before Any Cream

Clue	Detail	Basis
What set it off	Dark marks after acne stay where the acne was and can last a year or longer	Korean Dermatological Association, acne vulgaris · society
Melasma triggers and season	Gets worse with sun, pregnancy and birth control pills; darkens in summer and lightens in winter	Korean Dermatological Association, melasma · society
Where melasma usually shows up	The central-face pattern across the cheeks, forehead, upper lip, nose and chin is most common, followed by the cheek-and-nose pattern and the jawline pattern	Korean Dermatological Association, melasma · society
Color and depth	Shallow pigment looks brown, deep pigment looks blue-gray, and a mix looks gray-brown; a Wood’s lamp exam tells them apart	Korean Dermatological Association, melasma · society
Sun spots	Sun spots (solar lentigines) are studied as a separate condition from melasma and acne marks	2002 PMID 12077522 · A

The Korean Dermatological Association, Korea’s professional society of dermatologists, is the main source for this guide.

How do you tell acne dark marks from melasma, sun spots and moles?

At home, first write down when it appeared, where on your face it clusters, and whether it gets darker or lighter with the seasons. This way of sorting does not replace a diagnosis, and anything hard to tell apart by shape alone, like sun spots and moles, should be checked by a dermatologist.

How many laser sessions does hyperpigmentation take?

We found no source that fixes a number, and the Korean Dermatological Association says options like peels and lasers are chosen to fit each person’s skin. Even a 2023 meta-analysis pooling 6 randomized trials with 673 melasma patients (PMID 37457606) followed people for 8 to 24 weeks per study, so changes in pigment are judged over months.

Can a dermatology visit help with acne scars and dark marks?

A dermatologist checks whether it is a scar or pigment, and whether the pigment is shallow or deep, and then decides the approach. Clinical research also tracks progress over about three months, as in a 2023 randomized trial that followed 60 people with dark marks after acne for 12 weeks (PMID 37213446).

Pre-visit sorting log

What to note	Your case	Examples
When you first saw it and what set it off		After acne settled / during pregnancy or after starting the pill / no clear trigger
Location		A few spots on one cheek / wide on both cheeks and forehead / one spot on a sun-exposed cheekbone
Seasonal change		Darker after summer vacation / same all year
Color and edges		Pink / brown / blue-gray, and whether the edges are sharp
Sun		Hours working or exercising outdoors, number of days you wear sunscreen
What you have already applied		Exact product names and how long you used them

While you keep the log, do not scratch the patches or squeeze pimples. A 2021 study on risk factors for dark marks after acne (PMID 34880967) named too much sun and squeezing or picking, and the Korean Dermatological Association recommends sunscreen with SPF 30 or higher.

When should a dermatologist see the spot?

• If brown patches spread widely on both sides of your face where you never had acne, have a dermatologist check them.
• If something that looks like a mole changes in size, color or shape, do not wait; see a dermatologist.
• If patches got darker during pregnancy or after you started birth control pills, mention it at your visit.
• If an area you put something on turns red or stings, stop right away and talk to a dermatologist or pharmacist.

Evidence in short

• A 2023 meta-analysis pooling 6 randomized trials with 673 melasma patients (PMID 37457606) followed people for 8 to 24 weeks depending on the study.
• In a 2024 randomized trial comparing 49 women with melasma over 60 days (PMID 39376788), scores in both groups gradually improved, with no significant difference between groups at day 14 or day 60.
• The Korean Dermatological Association says melasma takes at least 2 months to show a response and 6 months or more overall.