Skin Hyperpigmentation: Types and Causes
I am a dermatologist in Miami Florida, so I see patients often with areas of hyperpigmentation.
Most causes of abnormal dark skin can be treated with skin lighting skin care products.
However you will get better results if you identify the cause of the skin hyperpigmentation.
What are the causes of the different types of skin hyperpigmentation disorders?
What is hyperpigmentation?
The definition of hyperpigmentation is an excess of pigment that leads to an uneven skin tone.
Hyperpigmented skin is darker than surrounding areas of skin.
Most types of hyperpigmentation are due to an excess of the skin pigment melanin.
What skin type is prone to hyperpigmentation?
Skin types that are quick to produce melanin are more likely to develop hyperpigmentation.
Skin Types prone to hyperpigmentation are:
- Fitzpatrick Skin Types 3,4,5 and 6
- Baumann Skin Types 1,3,5,7, 9,11,13 and 15
Which skin type are you?
Can white people get hyperpigmentation?
Yes all skin colors can get hyperpigmentation but it is more likely in darker skin types. It is very uncommon in redheads.
What does hyperpigmentation look like?
Hyperpigmentation from melanin looks like dark patches on the skin that can be light brown, dark brown, grey or black.
It causes an uneven skin tone.
The main causes of hyperpigmentation are:
- sun exposure
- light exposure
- increase in melanin stimulating hormone
- estrogen hormones
What triggers hyperpigmentation?
Melanocyte stimulating hormone (MSH) triggers the melanocyte to make melanin.
One way that MSH makes melanin is by activating the enzyme tyrosinase.
What skin pigment causes hyperpigmentation?
Melanin is the most common pigment to cause hyperpigmentation. This pigment gives a red brown or brown black color to the skin that varies depending on the type of melanin.
Bruises can cause hyperpigmentation due to deposition of hemosiderin which leaves a grey, blue-violet color on the skin.
Oral colloidal silver can leave a blue pigment in the skin.
Oral tetracycline can leave a dark blueish brown pigment on the skin.
Because melanin is by far the most common cause of hyperpigmentation, this blog will concentrate on the types of hyperpigmentation due to an excess amount of melanin.
What are the types of skin hyperpigmentation?
There are 4 main types:
- Post inflammatory hyperpigmentation
- Skin Tanning
- Sun spots
What is the most common hyperpigmentation?
A suntan is the most common form of hyperpigmentation.
The second most common for is post inflammatory hyperpigmentation that occurs from acne.
What type of hyperpigmentation is hardest to treat?
Melasma is the hardest type of hyperpigmentation to treat. This stubborn condition tends to recur.
Hyperpigmentation vs melasma
Melasma is a type of hyperpigmentation.
Hyperpigmentation on the face, arms or chest is a symptom of melasma.
Can hyperpigmentation go away?
If you change your habits, limit sun exposure, and add skin lightening ingredients to your skin care routine, the excess pigment will go away.
Why is it so hard to treat hyperpigmentation?
The reason that melanocytes product pigment is to protect your skin from sun. Melanin reflects away the sun's harmful radiation, helping to prevent DNA damage and skin cacner.
Your body has evolved to have this protective function.
This is why it is so hard to get rid of excess skin melanin.
When melanin is confined to the epidermis, it is easier to get rid of it with exfoliants.
Melian in the dermis is deeper and difficult to remove.
How to know if my hyperpigmentation is epidermal or dermal?
When melanin is deep in the dermis, it can take a skin care routine much longer to work.
There are 2 ways to tll:
Visualizing the skin with a camera such as the Canfield Viia camera
Shining black light on the skin which makes the melanin fluoresce.
Your dermatologist can use these technologies on your skin to tell you if your melanin is in the superficial epidermal layers or deeper in the dermis.
3 Types of Hyperpigmentation on the Face
Discoloration of the skin on the face is very common on the face because of sun exposure.
The 3 most common causes of a dark face are:
- Spots from acne
- Sun spots
Hyperpigmentation on the neck
Discoloration on the neck is almost always caused by sun. The exception is acanthosis nigricans which has a velvety texture.
The other causes of a dark neck are:
- Poikiloderma of Civatte
- Perfume use on neck that increases neck tanning
- Drugs that make you sun sensitive
Phytophotodermatitis occurs when you touch your skin with fragrances or certain foods that make skin sun sensitive. The most common causes are perfumes, lime juice, celery and figs.
Hyperpigmentation on back
Is your skin darker on your back? This is usually caused by post inflammatory hyperpigmentation from acne, folliculitis' or a rash.
Make sure you wear a shirt that has a UPF of 50+ when in the sun.
This is why you may develop dark patches of skin in areas where you had eczema.
To treat dark patches from eczema this you need to:
- treat eczema with a prescription medication or eczema cream
- use a barrier repair moisturizer
- Choose a cleanser that is safe for eczema-prone prone skin that does not foam.
Hyperpigmentation around the mouth
Darkness around the mouth occur when the perioral skin is irritated or inflamed.
The most common causes of dark skin around the mouth are:
- melasma (upper lip)
- perioral dermatitis (around the entire mouth)
When pimples heal they often leave behind dark pigment resulting in dark spots on the skin where a pimple was.
This occurs because Inflammation trigger the production of skin pigment.
Hyperpigmentation on lips
Dark lips can be your normal skin color.
Lips has less sun protection because they do not make sebum. This makes them more likely to burn and develop increased pigmentation.
Choose a lip balm with SPF to treat lip darkening of the lip lines.
Hyperpigmentation on the upper lip is usually due to melasma. See hyperpigmentation around the mouth discussed above.
Pigmentation on the forehead
A dark forehead is almost always caused from sun exposure.
Make sure you are not forgetting to apply sunscreen to your forehead.
If SPF burns your eyes when you sweat, avoid the sunscreen ingredient avobenzone.
Hyperpigmentation on legs
Sun exposure is not the only that that causes darkness on leg skin. Medications that make skin sun sensitive can also cause this.
Other causes of dark leg pigmentation are:
- heat and infrared light
- recent rash
- Schamberg’s disease
- Venous insufficiency
References and Scientific publications about hyperpigmentation:
- Gutierrez, D. Ch. 20Skin Pigmentation Disorders in Baumann's Cosmetic Dermatology 3rd edition (McGraw Hill 2022)
- Baumann, L Ch. 14 Uneven Skin Tone in Baumann's Cosmetic Dermatology 3rd edition (McGraw Hill 2022)
- Baumann, L Ch. 32 and 33 in Baumann, L Cosmeceuticals and Cosmetic ingredients (McGraw Hill 2015)
- Hadley, M. E., Heward, C. B., Hruby, V. J., Sawyer, T. K., & Yang, Y. C. (1981). Biological actions of melanocyte-stimulating hormone. Peptides of the Pars Intermedia, 244.
- Choudhary, R., Sharma, A., Kumar, S., Upadhyay, R. C., Singh, S. V., & Mohanty, A. (2020). Role of alpha-melanocyte stimulating hormone (α-MSH) in modulating the molecular mechanism adopted by melanocytes of Bos indicus under UVR stress. Molecular and Cellular Biochemistry, 465(1), 141-153.