The skin is composed of two layers, the epidermis (superficial layer) and the dermis (deep layer). Hyperpigmentation, which is characterized by the darkening of skin due to overproduction of the pigment melanin, can occur in both of these layers. Knowing in which layer the excess pigment lies is essential to developing the best and most efficacious treatment plan.
Epidermal vs Dermal Hyperpigmentation: What’s the Difference?
Distinguishing the difference between epidermal and dermal hyperpigmentation is quite simple. In natural UV light, epidermal pigmentation appears light to medium brown, while dermal pigmentation most often appears dark brown, blue or gray.
Another way to distinguish between the two is through a Wood’s lamp, which is an incredibly useful diagnostic tool found in most dermatologists’ offices. This lamp emits a black light (short wave ultraviolet light) which is invisible to the naked eye, but glows violet in a dark environment. It effectively determines the depth of melanin in the skin by highlighting the color contrast of pigmentation lesions. Epidermal pigmentation will fluoresce under a Wood’s Lamp, showing clear contrast (deeper color) while dermal pigmentation will not fluoresce, showing little to no change in contrast.
Epidermal Hyperpigmentation Defined
Epidermal hyperpigmentation refers to increased melanin deposition in the uppermost layer of the skin. It is typically short lived and easily treated with a regimen that comprises adequate sun protection, chemical exfoliators (alpha hydroxy acids) and melanogenesis suppressing ingredients such as vitamin C, tyrosinase inhibiting plant extracts (licorice extract, rumex extract, bearberry extract), and niacinamide (inhibits melanosome transfer from melanocytes to keratinocytes in the basal layer of the epidermis).
Dermal Hyperpigmentation Defined
Pigment that has reached the dermal layer is far greater to remove than pigmentation found in the epidermis. Topical skin lightening products are of little use as they cannot penetrate the dermis. Treatment of dermal hyperpigmentation instead requires the use of lasers and/or medium-depth chemical peels.
Medium-depth chemical peels involve the use of chemical agents (trichloracetic acid, Jessner’s solution, glycolic acid, or solid carbon dioxide) to wound the skin in a controlled manner, triggering regenerative processes that subsequently result in the healing and treatment of various skin disorders in the epidermis and papillary dermis. The gold standard for medium-depth peels have become a combination of the chemical agents listed above. Examples include:
- 70% glycolic acid + 35% trichloracetic acid
- Jessner’s solution + 35% trichloracetic acid
- Solid carbon dioxide freezing + 35% trichloracetic acid
Like with most skin peeling treatments, medium-depth chemical peels require a series of treatments to remove dermal pigmentation as well as downtime.
Mixed (Combination of Epidermal and Dermal)
Hyperpigmentation that occurs in both the epidermis and dermis requires a multifaceted combination approach that consists of topical skin lightening products and lasers or medium-depth chemical peels.
Bottom Line
Determining the location of melanin deposition in the skin can be achieved by the naked eye or the Wood’s lamp and helps to provide a clear diagnosis and the correct treatment plan.
How to Fight Hyperpigmentation
No matter what textbook, scientific definition there is one thing is for certain – hyperpigmentation is a bit of a curse. It’s the primary culprit behind dark spots, the darkening of underarms, knees, and other parts of the body, and is just generally frustrating to deal with.
Thankfully, we do have a variety of treatment options available to us that give us the ability to significantly reduce or completely get rid of dark spots caused by hyperpigmentation.
On the higher-end you’ll find a number of laser and surgical options to explore. These include laser removal treatments such as PiQ, YAG, or Picoway lasers used to fade the appearance of dark pigmentation. This method typically involves multiple sessions (each costing $150 or more), can’t be performed on all skin types, and can be a bit of a pain to schedule depending on the medical spa or dermatologist you’re getting treatment from.
Peels tend to work just as well and are a more cost-effective method of dealing with dark spots, but they can also address other issues such as acne and scarring.
If you’re looking for a very affordable, easy way to get hyperpigmentation under control that you can do yourself in the comfort of your own home (and still get great results) – we highly recommend using a skin lightening cream or brightening serum.
There are plenty to pick from, but, based on our research the best products to try are Meladerm Pigment Reducing Complex (our top pick that scored insanely well across the board), Alchimie Forever Pigment Perfecting Serum (one of our favorites and also one of the most popular), or La Roche-Posay Pigmentclar Dark Spot Corrector.