Although genetics and other factors play roles in pigmentation, there are other things that can change the balance of melanin in your body. This can include hormones, infections, and environmental changes.

This article will explore what can cause your skin to grow darker, or become hyperpigmented—especially around the mouth—and what you can do about it.

Causes of Hyperpigmentation Around the Mouth

Melanin is a primitive black or dark brown pigment that exists at some level in most living things. Its ability to absorb a variety of radiation types gives melanin a protective quality, but there are times when your body can produce too much of it.

Melasma

Hormones can trigger melanin production, especially during pregnancy. Melasma is the name of this condition, which occurs in pregnancy—mostly in women who already have darker skin. In fact, melasma is so common in pregnancy, it’s often referred to as the “mask of pregnancy.”

About a third of all pregnant women develop this condition, which causes splotchy areas of dark patches primarily on the face, such as the forehead, cheeks, and upper lip. However, as many as 10% of women also go on to develop this condition after another major hormonal change—menopause.

Certain Medications

All kinds of chemicals and medications can alter the cells that produce melanin in your body. In some cases, these substances can damage melanin production, resulting in lighter areas of skin.

When medications cause hyperpigmentation, they usually cause areas of your skin to turn darker. Some examples of medications that have been linked to hyperpigmentation include:

Nonsteroidal anti-inflammatory drugs (NSAIDs) Medications to treat high blood pressure including Micardis (telmisartan) and Capoten (captopril) Anticonvulsants like Tegretol (carbamazepine) and Lamictal (lamotrigine) Antimalarial drugs like hydroxychloroquine Antibiotics like tetracycline and minocycline or doxycycline Antineoplastic drugs that treat things like cancer, including Cytoxan (cyclophosphamide), ifosfamide, and thiotepa Psychoactive medications like chlorpromazine and tricyclic antidepressants Zocor (simvastatin) Zyloprim (allopurinol) Amiodarone Mucolytic medications Heavy metals like silver, gold, and iron

Sun Exposure

Exposure to ultraviolet radiation is also a common cause of increased melanin resulting in hyperpigmentation. Although there are many sources of ultraviolet light, exposure to the sun is one of the most commonly encountered sources, and hyperpigmentation is often found in areas of the skin that are exposed to sunlight. Tanning beds can also increase your risk of dark spots as you age.

Trauma to the Skin

Injuries are another possible cause of hyperpigmentation. Called post-inflammatory hyperpigmentation, darker areas that appear after injury or irritation can take a long time to resolve.

In addition to injuries, this type of hyperpigmentation can also develop from other sources of inflammation, including autoimmune disorders and infections. Acne is one of the most common causes of post-inflammatory hyperpigmentation in people with darker skin colors, developing in about 65% of people of color with acne.

Some possible sources of hyperpigmentation that can result from inflammatory conditions like:

Acne vulgaris Atopic dermatitis Impetigo Viral exanthems Fungal infections Contact dermatitis Scleroderma Sarcoidosis Systemic lupus erythematosus Dermatomyositis Insect bites Psoriasis Lichen planus Pityriasis rosea Lichen simplex chronicus Burns Cryotherapy Chemical peels Radiation therapy Mycosis fungoides Erythema dyschromicum perstans

In and around the mouth in particular, the following can contribute to hyperpigmentation problems:

Drugs and medications Tobacco HIV Tuberculosis Candidiasis Heavy metal exposure Graphite Pregnancy Thyrotoxicosis Hemochromatosis Neurofibromatosis Peutz-Jeghers syndrome Laugier-Hunziker syndrome LAMB syndrome and LEOPARD syndrome Oral melanoacanthoma Birthmarks Freckles or moles Skin cancer

Vitamin Deficiencies

Metabolic disorders and imbalances are other common causes of hyperpigmentation. This can include diseases like Addison’s disease, which affects the adrenal glands, as well as vitamin deficiencies and other metabolic issues.

Cortisol is made by the adrenal glands, explaining the relationship to Addison’s disease, but other metabolic diseases can also play a role. Adrenocorticotropic hormone (ACTH)—produced by the pituitary gland—and thyroid disorders have also been linked to hyperpigmentation.

In addition to diseases and hormone imbalances, deficiencies in the following can also lead to hyperpigmentation:

Vitamin B Folic acid Iron

Treatment

In many cases, time is the best healer of hyperpigmentation. Especially for dark spots that form as a result of injury or inflammation, hyperpigmentation will usually fade in time, although it can take months to years.

If you are looking for a topical treatment that can even skin tone to reduce the appearance of hyperpigmented areas, you can look for skin care products that contain the following ingredients:

Azelaic acid Glycolic acid Kojic acid Retinoids like retinol, tretinoin, adapalene gel, or tazarotene Vitamin C

Many of these substances work by slowing the production of melanin, which contributes to or causes hyperpigmentation.

If the topical products you are using are not helping your hyperpigmentation, your doctor or dermatologist can offer you other prescription-strength options.

Prevention

The best way to prevent hyperpigmentation is to protect your skin from what you can. Though you really can’t avoid every cause of hyperpigmentation, avoiding excessive sun exposure can help ward off dark spots.

In particular, dermatologists recommend the following tips to prevent hyperpigmentation:

Apply sunscreen every two hours while outdoors Reapply sunscreen after sweating or swimming Wear a wide-brimmed hat outdoors Avoid being in the sun when it is strongest, usually between the hours of 10 a. m. and 2 p. m. Avoid using skin care products that are harsh and burn or sting when applied

When choosing a sunscreen, the following types offer the best protection to avoid developing areas of hyperpigmentation:

SPF 30 or higher Broad-spectrum protection Water-resistant formulas Either titanium dioxide and/or zinc oxide as one of the ingredients

When to See a Healthcare Provider

See your doctor if you have an area of hyperpigmentation that is not going away with treatment from over-the-counter products. Prescription-strength formulas can give you the same ingredients, like retinoids, at stronger doses.

Talk with your provider if you have other symptoms that could signal the presence of a body-wide condition that is causing hyperpigmentation, such as Addison’s disease or a vitamin deficiency. Finally, if the dark area includes a mole or freckle with a concerning shape or pain, talk to your doctor about screening for skin cancer or other dermatological problems.

Summary

There are many reasons you could develop dark spots on your skin, especially around the mouth. In many cases, these dark spots will fade with time, but there are also over-the-counter and prescription skin care products that can help fade areas of hyperpigmentation. Talk to your doctor or dermatologist to figure out your diagnosis and the best treatment plan.

A Word From Verywell

Dark spots on your skin can develop for a number of reasons, and most are not serious. Protecting your skin from the sun can go a long way toward preventing areas of hyperpigmentation, and if these spots do develop, most will fade with time.

Talk to your healthcare provider if you have dark areas of skin that are getting worse or appear with pain and other symptoms.