The Four Types of Hyperpigmentation and What Causes Them

I was surprised when “freckles” showed up in the types of hyperpigmentation, but it makes sense. Anything tthat causes extra melanin (skin pigment) is a type of hyperpigmentation.

There are several sub-types of hyperpigmentation, including:

• Melasma
• Post-Inflammatory Hyperpigmentation (PIH)
• Lentigines (Age Spots or Liver Spots)
• Freckles

Plus, there are many causes of extra melanin, and therefore, many ways to combat dark spots. The causes of hyperpigmentation include:

• Genetic Predisposition
• Sun Exposure
• Other Ultraviolet Light Exposure
• Hormonal Changes
• Acne, Eczema, and Skin Injuries
• Medication Side Effects or Allergies

What is Hyperpigmentation?

Hyperpigmentation is the darkening of skin in areas or patches due to excess melanin. The dark melanin is the pigment that gives color to the skin, as well as to the hair and the eyes.

Hyperpigmentation can occur anywhere on the body. It is mostly likely to occur on areas of frequent sun exposure, which are the face, neck, hands, and arms.

There are several ways to get excess pigmentation, and several ways to make it go away. Understanding the underlying causes will help direct your treatment approach.

Types of Hyperpigmentation

The types of hyperpigmentation are all disorders of melanin. The difference is what triggers the overproduction in certain spots. The types of hyperpigmentation are:

• Melasma
• Post-Inflammatory Hyperpigmentation (PIH)
• Lentigines (Age Spots or Liver Spots)
• Freckles

Melasma

Melasma is a common skin condition characterized by dark, patchy areas of pigmentation on the face. The spots usually show up on cheeks, forehead, chin, and upper lip.

Melasma is more common in women than men, especially because it is associated with oral contraceptive use and pregnancy. Some men and women develop melasma even when not affected by hormonal medications and events.

Melasma appears to have a number of causes. These include genetics, hormonal changes, sunlight exposure, ultraviolet light exposure, and taking certain medications. Anti-seizure drugs and cosmetics can trigger melasma.

Melasma causes dark, irregular patches on the face. They are tan, brown, or gray.

Melasma treatment options include medications, and dermatological procedures. Medications include hydroquinone, tretinoin, and corticosteroids, which can help to lighten the skin and reduce the appearance of dark patches. Chemical peels, microdermabrasion, and laser therapy stimulate collagen production and rejuvenation to light dark spots.

Post-Inflammatory Hyperpigmentation (PIH)

Post-inflammatory hyperpigmentation (PIH) is a common skin condition that occurs when the skin produces excess melanin in response to inflammation or injury. This can result in dark spots or patches of hyperpigmentation that are often darker than the surrounding skin.

PIH can be caused by a variety of factors, including acne, eczema, psoriasis, dermatitis, insect bites, or other forms of skin injury or irritation. When the skin is inflamed or injured, it triggers the production of melanin, which can cause the skin to become darker in color.

Symptoms of PIH include the appearance of dark spots or patches of hyperpigmentation on the skin, which may be flat or slightly raised. These patches may be brown, black, or gray in color and may be more pronounced on areas of the skin that are exposed to the sun.

PIH treatment options are the same as those for melasma. Hydroquinone, tretinoin, and corticosteroids lighten the skin and reduce the appearance of dark patches. Chemical peels, microdermabrasion, and laser therapy cause collagen production and skin rejuvenation to lighten dark spots.

The key to PIH is resolving the underlying inflammation. When that calms down, PIH is easier to attack and remove.

Lentigines (Age Spots/Liver Spots)

Lentigines, also known as age spots or liver spots, are small, flat, and brown patches of skin. You usually see age spots on areas exposed to the sun such as the hands, arms, face, and neck.

Age spots often occur in people over of age of 50. The current thinking is that sun (and other ultraviolet light) exposure is involved increasing age spots. They might be the result of glycation, which is when glucose impairs a protein molecule. They can occur in younger people. Age spots are excess melanin.

Treatment options for lentigines include topical medications, such as hydroquinone, tretinoin, or azelaic acid, which can help to lighten the skin and reduce the appearance of age spots.

Other treatments may include chemical peels, microdermabrasion, or laser therapy.

Freckles

Freckles are small, flat, and brown spots that appear on the skin, particularly on areas of the body that are exposed to the sun, such as the face, arms, and shoulders. They are usually harmless and are more common in people with fair skin.

The exact cause of freckles is not fully understood, but current thinking is that freckles are a melanin response to ultraviolet light exposure. Freckles are excess melanin.

Freckles may be more pronounced in the summer months when the skin is exposed to more sunlight.

Treatment options for freckles include topical medications, such as hydroquinone or tretinoin. They light the skin to reduce the appearance of excess melanin.

Other treatments may include chemical peels, microdermabrasion, or laser therapy. However, it is important to note that freckles are generally harmless and do not require treatment for medical reasons.

The best way to prevent freckles is to protect the skin from the sun by wearing protective clothing, such as hats and long-sleeved shirts, and using sunscreen with a high SPF. Avoid tanning beds and other sources of UV radiation, as these can increase the risk of developing freckles and other skin conditions.

What Causes Hyperpigmentation?

The sun’s ultraviolet light is just one cause of dark spot. There are several underlying causes to hyperpigmentation, including:

• Genetic Predisposition
• Sun Exposure
• Other Ultraviolet Light Exposure
• Hormonal Changes
• Acne, Eczema, and Skin Injuries
• Medications

Genetic Causes of Hyperpigmentation

Genetics can contribute to the development of hyperpigmentation.

Certain genes may make an individual more prone to developing hyperpigmentation. Individuals with darker skin tones have more melanin in their skin. The melanin is inherited through genetics. More melanin can mean a tendency toward developing hyperpigmentation.

Genetics can also trigger albinism, which affects the distribution of melanin. This can also present as dark spots.

Sun Exposure Causes Hyperpigmentation

Sun exposure can cause hyperpigmentation in people with lighter skin tones (those with less melanin).

The exposure triggers melanin production as a defense against ultraviolet radiation. The extra melanin can darken the skin over time. This form of hyperpigmentation usually happens on the face, the arms, and the hands.

Ultraviolet rays from the sun can damage skin cells, creating dark spots on the skin. Sun exposure can also exacerbate existing hyperpigmentation, making it appear more prominent or widespread.

Hormonal Changes Can Cause Hyperpigmentation

Hormonal changes can contribute to hyperpigmentation in several ways.

Pregnant women can experience melasma, which presents as brown patches on the face, neck, and arms. Pregnancy increases estrogen and progesterone levels, which stimulate melanin production.

Hormonal changes associated with the use of oral contraceptives or hormone replacement therapy can also contribute to the development of hyperpigmentation, particularly in individuals with a history of melasma.

Additionally, hormonal changes associated with menopause or thyroid disorders can cause changes in skin pigmentation, leading to hyperpigmentation or hypopigmentation.

Acne, Eczema, and Skin Injuries Can Trigger Hyperpigmentation

Inflammation can contribute to hyperpigmentation in several ways.

Acute inflammation is a natural and healthy response to injury and infection. The body responds to acne, eczema and psoriasis with inflammation to fight off the disorder. That inflammation can trigger melanin to complement the healing process. That leads to dark spots.

Additionally, inflammatory conditions such as lupus or certain autoimmune diseases can cause changes in skin pigmentation, leading to hyperpigmentation or hypopigmentation.

Finally, inflammation resulting from skin injuries or trauma, such as cuts, burns, or surgeries, can also contribute to the development of hyperpigmentation as the skin heals.

Medications Side Effects and Allergies Can Cause Hyperpigmentation

Certain medications can contribute to the development of hyperpigmentation. The dark spots can show up as a side effect or as an allergic reaction.

For example, some antibiotics, antimalarial drugs, and chemotherapy agents can cause hyperpigmentation as a side effect.

Additionally, medications such as non-steroidal anti-inflammatory drugs (NSAIDs) or tetracycline antibiotics can cause hyperpigmentation as an allergic reaction, known as fixed drug eruption.

The hyperpigmentation may appear as dark patches or spots on the skin, and may be localized to the area where the medication was applied or systemic.