Have you ever been frustrated that your melasma treatment isn't working? The real reason it might not be fading could be Ota nevus, deeply embedded in the skin, disguised as melasma. These two conditions differ in their cause and the location of the pigment, so approaching them with the wrong method can easily prolong treatment. Today, we will clarify the decisive differences between melasma and Ota nevus.
Different Onset Ages
Melasma and Ota nevus appear at different times. Melasma often develops in middle-aged women in their 30s and 40s, whereas Ota nevus is closer to a congenital condition. It usually begins at a young age and tends to darken progressively through elementary and middle school.
Different Colors and Locations
There are also differences in color.
- Melasma often appears brownish.
- Ota nevus is characterized by a bluish tint and typically appears on one side of the face.
However, there's a point to note. In addition to congenital cases, there are also acquired Ota nevus, and it's not uncommon for melasma and acquired Ota nevus to coexist.
Melasma is classified as epidermal if it occurs between the epidermis and dermis, dermal if it occurs deeper in the dermis, and mixed if both are present.
Different Treatment Concepts
Treatment approaches also differ. Melasma often involves a mixed type, so it's approached with a long-term management mindset using lasers. Typically, laser toning is repeated every 2 to 4 weeks. Melasma has a strong concept of management because even if it improves to some extent, it can reappear with sun exposure or hormonal changes.
On the other hand, congenital Ota nevus is a therapeutic concept that involves using lasers to clear the causative pigment cells. It is usually repeated every one to two months, and lasers that act on pigment cells are more effective than toning.
Side Effects Should Also Be Known in Advance
Traditional methods of aggressive treatment are effective, but they can cause bruising in the treated area, interfere with daily life, and some individuals may struggle with post-inflammatory hyperpigmentation that turns brown. In such cases of acquired Ota nevus, repeated low-energy laser toning can also yield good results.
Why Does It Take Over a Year?
Neither melasma nor Ota nevus can be resolved in a single session. Melasma requires consistent management due to its tendency to recur, and congenital Ota nevus requires treating pigment cells in multiple stages. Recently, the PicoWay Laser has been widely used for congenital Ota nevus as it is more effective. Therefore, accurate differentiation is the first step; repeating only one method without proper distinction can prolong the time and cost.
Results may vary by individual, and accurate diagnosis and treatment are determined after consultation.
By Dr. Lee Sang-joo, Chief Director (Yonsei Star Dermatology) · Medical Staff Introduction · Last reviewed 2026-06-03