First published: 2025-01-20 / Last reviewed: 2026-05-28
This is a guide to CO2 laser treatment for moles and seborrheic keratosis, compiled by Dr. Choi Byeong-geun of SHINE U Clinic Konkuk (3 minutes' walk from Konkuk Univ. Station, Exit 1).
Many people notice dark spots that bother them every time they look in the mirror, thinking they are just moles, only to find out they are seborrheic keratosis. This is a type of pigmentation that occurs due to a combination of aging and sun exposure. Let's organize the information in the order of questions a patient might have: why it occurs and how it is treated.
Why does seborrheic keratosis occur?
Seborrheic keratosis is primarily known to be caused by aging and sun exposure.
- Aging: A change where brown pigments increase as proteins and sugars in the skin combine.
- Ultraviolet rays: Prolonged exposure to sunlight can harden keratin or cause excessive cell proliferation.
- Genetic factors: Cases where family history plays a role.
It can appear not only on the face but also on areas frequently exposed to sunlight, such as the hands.
Why makeup can't cover it
Seborrheic keratosis often involves pigmentation that extends beyond the epidermis to the dermis, making it difficult for cosmetics to completely cover the deep pigmentation. Furthermore, the affected areas of seborrheic keratosis have a thicker and rougher stratum corneum than normal skin, which prevents makeup from adhering well. Even if it's covered immediately after makeup application, it often reappears over time.
How pigmentation lasers treat it
After a diagnosis suitable for the pigmented lesion, it is treated with a laser. Pigmentation lasers work by delivering energy to the pigmented area to treat melanin while minimizing damage to the skin. Many devices use a cooling method to prevent the surface temperature from rising during the procedure, designed to focus on the target area while reducing surface damage.
Many people worry about pain, but devices with added cooling technology are reported to have less pain, and daily life is relatively unaffected after the procedure. However, individual differences in pain perception may exist. Some devices also have a function to distinguish lesions so that energy does not affect normal skin other than the pigmented area, which can help precisely treat the problematic area.
"Is one treatment enough?" This is a frequently asked question. Due to differences in the depth and number of lesions, it is often difficult to treat them all at once, and you will be guided on the necessary number of sessions after checking your condition. Results may vary individually.
Post-treatment care and recurrence prevention
Post-treatment care is crucial for pigmentation procedures. If sun protection is neglected or external irritation is added, pigmentation can darken again or new spots may appear. It is helpful to have an experienced clinic check the depth and number of lesions and guide you systematically on the number of sessions.
Seborrheic keratosis is a type of pigmentation that is difficult to disappear naturally during the aging process. The depth and number of your seborrheic keratosis, and which method is suitable, are determined during a consultation with Dr. Choi Byeong-geun. If you have any questions, please leave a pigmentation consultation via chat.
If other pigmented lesions such as freckles, lentigines, or moles are present, PicoSure toning may also be considered to improve overall skin tone. It is important to treat not only the epidermis but also the dermis to reduce recurrence. If you are curious about a plan tailored to you, please feel free to inquire via chat consultation.
Authored by: Dr. Choi Byeong-geun (Chief Director of SHINE U Clinic Konkuk / Member of the Korean Academy of Laser Dermatology and Hair, Korean Academy of Aesthetic and Plastic Surgery Lasers, Korean Filler Society, etc.) Last reviewed: 2026-05-28
This article is for general information on procedures and does not replace diagnosis or treatment. Suitability and results of procedures may vary individually.