Your nails can tell you a lot about your health. The skin under and around your nails are susceptible to many diseases. Warning signs of other health problems also can appear on your nails.

Good nail care is important because it helps prevent many common nail conditions. In addition to taking good care of your nails, see a board-certified dermatologist if you notice any of the following symptoms on your nails or the skin around them.

WHAT IS AN INGROWN NAIL?

When the corner of a nail curves downward into the skin, it causes an ingrown nail. Ingrown nails are most common on the big toe. An ingrown nail may be caused by not cutting the nail straight across, tight shoes, poor hygiene, injury or even a genetic predisposition.

An ingrown nail can be painful and can become infected. Treatment can help these problems.

Fungal nail infection

Fungal nail infection

WHAT ARE THE SYMPTOMS OF AN INJURED NAIL?

A fine red to reddish-brown vertical line under your nail may be caused by an injury with bleeding under the nail. This is known as a splinter hemorrhage. Some medicines and medical conditions can also cause reddish lines to appear on the nails, so see a board-certified dermatologist if you notice a new red line.

Minor nail injuries commonly result in small white spots. They typically disappear on their own as the nail grows out and do not require treatment. You should, however, see your dermatologist if you see many white spots and do not remember injuring your nail, or if the white spots do not grow out. This could mean you have an infection or another medical condition.

WHAT DOES A FUNGAL NAIL INFECTION LOOK LIKE?

When nails are infected by a fungus, they often become thicker and discolored. You also may notice flakes under the nail, white or yellow streaks on the nail, or crumbling at the corner or tip of the nail. Nails also may split or lift away from the skin.

When caught early, a fungal nail infection may clear with a topical (applied to the nail) antifungal treatment. Many fungal nail infections, however, require medicine that works throughout the body. Your dermatologist may prescribe an antifungal medicine that comes in pill or liquid form. Laser procedures also may be used to treat the nail.

It’s important to see a board-certified dermatologist before starting any treatment for a suspected fungal nail infection.

Other conditions may look like nail fungus, and you should not use an antifungal treatment if you don’t have a fungal infection.

WHAT ARE THE SYMPTOMS OF A BACTERIAL NAIL INFECTION?

A bacterial nail infection most commonly forms after the nail or surrounding skin is injured. This type of infection can cause redness, swelling or pain. Pus also can accumulate in the skin around the nail, and the nail can develop a greenish color.

If you have a bacterial nail infection, treatment is important. A dermatologist often will drain the pus and prescribe

an antibiotic.

WHAT DOES NAIL PSORIASIS LOOK LIKE?

Psoriasis is a skin condition that can affect the nails, causing pits, ridges and discoloration. The skin beneath the nail can turn reddish brown. Reddish lines may appear. The nails can crumble, split and separate from the skin.

These nail changes can occur in people with any type of psoriasis. Sometimes, nail changes are the first sign of psoriatic arthritis, a type of arthritis that some people who have psoriasis can develop. Nail psoriasis can affect one or more nails, and it may be painful. Various treatments, including phototherapy, systemic medications and cortisone injections, can help manage nail psoriasis.

CAN NAILS GET SKIN CANCER?

Many different types of skin cancer, including melanoma and squamous cell carcinoma, can form under or around a nail. If you see a growth in these areas, see a board-certified dermatologist. Skin cancer is highly treatable when detected early.

Melanoma, the deadliest form of skin cancer, may appear as a dark streak or spot on the nail. People with skin of color are prone to this type of melanoma. Many nail streaks are harmless, and they are common in people of color. However, it’s important to see a board-certified dermatologist if you notice a dark streak or spot on your nail and you don’t remember injuring it.

Melanoma under the nail

Melanoma under the nail

WHAT KIND OF GROWTHS CAN OCCUR AROUND THE NAILS?

A growth on the skin surrounding a nail is often a wart. Warts are common on the hands and feet. When warts develop near a nail or grow under the nail, they should be treated. Treatment can get rid of the wart, enabling you to use the finger or toe normally. Dermatologists offer a variety of treatments for warts.

Jelly-like growths called mucinous cysts can appear on the skin above the cuticle. These cysts can be painful. If allowed to grow, a cyst can damage nail or cause it to become deformed. A board-certified dermatologist can recommend the right treatment for this type of cyst.

COULD NAIL SYMPTOMS INDICATE OTHER HEALTH CONDITIONS?

Changes to our nails often help doctors find diseases, some of which could be serious. If you notice any changes in the appearance of your nails, see a board-certified dermatologist.

HOW CAN I TAKE GOOD CARE OF MY NAILS?

Poor nail care can cause nail problems. To keep your nails healthy, dermatologists recommend the following:

  • Keep your nails clean and dry. This helps prevent nail infections. Wear breathable socks, and use flip-flops at public pools, gyms, locker rooms and
  • Cut your toenails and fingernails straight across, rounding slightly in the center. This keeps your nails

strong and helps prevent ingrown toenails.

  • Keep your toenails short. This minimizes the risk of nail
  • If your toenails are thick and difficult to cut, soak your feet in warm salt water (1 teaspoon of salt per pint of water) for five to 10 minutes. After drying your feet, apply a cream that contains urea or lactic acid to soften the skin and
  • Smooth rough edges with an emery board. This helps prevent nails from snagging, reducing your risk of nail injury. To avoid an infection, do not share emery boards. If you visit a nail salon, make sure the equipment is sterilized.
  • Avoid biting your nails. Nail biting can not only ruin the look of your nails, but also damage the skin around your

nails, increasing the risk of infection. Avoiding the temptation to bite your nails is especially important if you have or are prone to nail disease. To help patients stop nail biting, dermatologists often recommend applying a bad-tasting nail polish. Behavioral therapy also may help break this habit.

  • Protect your cuticles. Cuticles prevent bacteria and other germs from entering our bodies. To protect your cuticles, never cut them or forcefully push them back, and do not allow nail salon technicians to do so. If you must push back your cuticles, only do so gently after a shower or
  • Do not try to “dig out” an ingrown toenail, as this could cause an infection or make an existing infection worse. See a board-certified dermatologist for the treatment of ingrown
  • Wear shoes that fit properly. Alternate the shoes you wear each
  • If you have diabetes or poor circulation, pay close attention to your feet and nails. At the first sign of a

problem, see your dermatologist.

WHEN SHOULD I SEE A DERMATOLOGIST ABOUT MY NAILS?

If allowed to progress, nail disease can be challenging to treat. Early diagnosis and proper treatment offer the best outcome. If you notice unusual or bothersome changes in your nails, see a board-certified dermatologist for evaluation and treatment, if necessary.

A board-certified dermatologist is a medical doctor who specializes in the diagnosis and medical, surgical and cosmetic treatment of skin, hair and nail conditions. To learn more about nails or to find a board-certified dermatologist in your area, visit aad.org/nails or call toll-free (888) 462-DERM (3376).

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Images used with permission of the American Academy of Dermatology National Library of Dermatologic Teaching Slides

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