An Overview of Dark Spots

Dark spots on the skin can happen at any time but most commonly appear in middle age. They are most often a result of cumulative exposure to sunlight or artificial ultraviolet (UV) light used in tanning beds.

The spots are also associated with certain skin conditions and can be a side effect of some medications.

This article explains the symptoms, diagnosis, and treatment of dark spots on the face and body.

Dark Spot Symptoms

Dark spots are generally harmless, but there are times when they could be cancerous. If they bother you, they can be lightened or removed.

These spots can range from light to dark brown or black in color. They are flat and generally oval-shaped.

Dark spots can develop anywhere. But they are most likely to appear on parts of the body that receive the most sun exposure. These include:

• Face
• Backs of the hands
• Shoulders
• Arms
• Back

While individual spots are usually small, several can group and form larger areas of darkened skin.

Causes

Dark spots are the result of the overproduction or collection of melanin, a skin pigment that makes skin darker. They can also result from free radical damage.

Exposure to UV Light

The sun and tanning beds are the most significant cause of dark spots.

Hyperpigmentation often appears during middle age. That's when the skin starts to show the consequences of sun exposure. This is especially true if you didn't use sunscreen and other sun-protective measures consistently earlier in life.

People with light hair or skin and who have had many sunburns, or severe ones, are at particular risk.

However, other things may lead to dark spots. These other causes may act alone or in combination with UV exposure.

Skin Conditions

There are several different skin conditions and diseases that can cause dark spots. However, these are not the same as age-related dark spots. They include:

• Post-inflammatory hyperpigmentation: Skin discoloration following a scrape, rash, or acne
• Melasma: Also known as pregnancy mask or chloasma
• Linea nigra: A dark, vertical line that appears lengthwise down the middle of the abdomen during pregnancy
• Riehl's melanosis: A form of contact dermatitis that's believed to be caused by sun exposure
• Poikiloderma of Civatte: A benign (non-cancerous) condition that turns parts of the neck a reddish-brown color
• Erythromelanosis follicularis: A reddish-brown pigmentation of the face and neck

Medications

Certain medications can cause dark spots because they make the skin more sensitive to sun exposure (also known as photosensitivity). They include:

• Estrogens, such as Vagifem, Climara, and Estrace
• Tetracyclines, broad-spectrum antibiotics such as Adoxa (doxycycline), Declomycin (demeclocycline), and Minocin (minocycline)
• Amiodarone used to treat irregular heartbeat (brand names include Cordarone and Pacerone)
• Phenytoin, an anticonvulsant (brand names include Dilantin and Phenytek)
• Phenothiazines used to treat mental and emotional disorders (brand names include Compro and Thorazine)
• Sulfonamides used to treat infections (brand names include Bactrim and Septra)

Other Causes

Dark spots may also be seen in these conditions:

• Pregnancy
• Liver disease
• Addison's disease
• Hemochromatosis (excessive iron)
• Pituitary tumors

Diagnosis

Your primary healthcare provider or a dermatologist can usually diagnose dark spots with a physical examination. Unless a spot looks suspicious, a biopsy or further testing is not necessary. 

Treatment

Dark spots don't hurt, and they have the same texture as the rest of your skin. Most of the time, they don't pose any health risks. So you don't have to get rid of them, although many people choose to for cosmetic reasons.

Dark spots can be faded or removed completely with prescription drugs, medical procedures, and at-home treatments.

Topical Treatments

Prescription bleaching creams gradually diminish the appearance of dark spots. This usually takes several months.

Hydroquinone is the active ingredient in prescription skin lightening creams. It works by reducing melanin production. However, long-term use has some risks, so you should only use it on a short-term basis.

Several other OTC products treat dark spots. They might lessen the appearance of spots but may not eliminate them. Look for creams that contain retinoids, alpha hydroxy acid, glycolic acid, deoxyarbutin, or kojic acid.

Cosmetic Procedures

Healthcare providers and estheticians can use medical procedures to treat dark spots on any part of the body. They are often used along with topical treatments. However, some may not be appropriate for people with sensitive skin. Options include:

• Laser treatment: This uses focused light energy to remove skin layer-by-layer, which burns off dark spots. Risks include bruising, swelling, redness, tightness, scarring, infection, and changes in skin texture.
• Chemical peels: These contain salicylic acid and/or glycolic acid, which remove the top layer of skin. This may result in healthier and more evenly toned skin beneath. However, skin irritation is a possible risk.
• Microdermabrasion: There are two types of microdermabrasion. Both physically remove cells on the surface of the skin. With crystal microdermabrasion, a machine sprays fine crystals through a wand that rubs against the skin and scrapes away cells. For diamond-tipped microdermabrasion, the abrasive end of a wand is used for this purpose instead. The skin may be pink for a while afterward, but these techniques are considered low-risk.
• Cryosurgery: Cryosurgery fades age spots by freezing them with a liquid nitrogen solution. This causes the darkened skin to peel away from the body. Risks include permanent whitening of treated areas.

Prevention

As you age, dark spots may be inevitable. However, there are some ways to help avoid getting dark spots or prevent faded ones from returning. These include:

• Use SPF: Be diligent about wearing and reapplying sunscreen every two hours. Reapply more frequently if you've been swimming or sweating a lot.
• Cover up: When outdoors, wear a hat, long sleeves, and pants. SPF fabrics can offer added protection.
• Avoid peak sun hours: UV exposure is usually greatest between the hours of 10 a.m. to 2 p.m.

Summary

Dark spots commonly occur as people age. They are often the result of past sun exposure. But they can also be due to some skin conditions, medications, and certain medical conditions.

Often your healthcare provider or dermatologist can diagnose dark spots by looking at them. But in some cases, they may do a skin biopsy to be sure.

Dark spots are usually harmless. Even so, some people choose to have them removed for cosmetic reasons. Treatment options include skin lightening creams and cosmetic procedures.

You may not be able to prevent dark spots entirely. But, you can reduce your risk by using sunscreen, staying covered up when you are in the sun, and staying out of the sun during peak hours.

A Word From Verywell

Visit your dermatologist annually for a skin checkup, even if you think any oddities on your skin are harmless. Though a dark spot is likely nothing to worry about, remember that skin color changes can sometimes be a sign of cancer. That's particularly true when paired with other changes such as bleeding, itching, and redness.

In rare cases, what can appear as a sunspot such as a solar lentigo may, in fact, represent a type of melanoma called lentigo maligna. If your healthcare provider sees a potentially harmful dark spot, they can perform a biopsy to check for something more serious, like skin cancer.