Causes and Treatments for Black Toenails

A toenail turning black can be concerning, especially if you’re unsure what causes it or how to treat it. Whether you’re experiencing discomfort, are worried about its appearance or want to understand more about the condition, you’re not alone. Athletes, older adults and individuals going about their daily routines face this issue.

Black toenails can stem from a stubbed toe, an ingrown toenail, an underlying health condition or a fungal infection. You can treat a black toenail with antifungal medication or visit a podiatrist to perform a minor procedure to release trapped blood.

This post discusses why your toenail is black and your treatment options.

What Are Black Toenails?

As the name suggests, black toenails are a condition in which the nails turn dark. The discoloration can range from black or brown spots to covering the entire nail. The condition can signal health problems that require medical attention.

The following symptoms may accompany the discoloration:

• Pain or tenderness under the nail
• Swelling around the toenail
• Separation of the nail from the nail bed
• Thickened nails
• Odor
• Bleeding or discharge
• Brittle nails

What Causes Black Toenails?

Black toenails can stem from minor injuries to underlying health conditions. Here’s why your toenail turns black.

Trauma and Bruising

Trauma is the most common cause of black toenails. It occurs when the toenail experiences a sudden or repetitive force, which tears the tiny blood vessels beneath the nail bed. Stubbing your toe or dropping a heavy object on your foot can cause blood to pool under the nail, leading to a blackened appearance. Pain may be sharp, and localized and swelling may follow.

Athletes may develop black toenails because of consistent pressure from tight shoes or repetitive impact. This condition is sometimes called runner’s toe. The repeated force affects the nail bed, causing discoloration and discomfort.

Fungal Nail Infections and Ingrown Toenails

Fungi thrive in warm, moist environments such as sweaty socks and locker rooms. The fungus enters the nail or surrounding skin and then spreads into the nail. If debris is present under the nail, the nail may darken to a black or brown hue.

When the edges of the toenail grow into the surrounding skin, it creates an open wound. This allows bacteria or fungi to enter, causing infection and sometimes darkening the area under the nail. Poor nail-cutting techniques, tight shoes and toe injuries typically contribute to this condition. Redness, swelling and pain are typically early signs of an ingrown toenail. If the infection sets in, the area may ooze pus or blood, and the nail may become discolored.

Underlying Health Conditions

Black toenails can sometimes be a symptom of a deeper health issue, such as:

• Diabetes and poor circulation: Reduced blood flow to the legs and feet can weaken nails, making them susceptible to trauma or infection. Older adults may face this issue because of reduced blood circulation.
• Autoimmune disease: Psoriasis can also impact nail health, causing discoloration, thickening or pitting.
• Nutritional deficiencies: Though rare, vitamin B12 deficiency can cause nail beds to appear dark or purplish.

Medication

Certain medications can cause nail discoloration as a side effect:

• Chemotherapy: Because cells undergo various cycles during treatment, it may lead to nail changes, including darkened nails.
• Antibiotics: Tetracyclines may cause photosensitivity in the nails.

Melanoma

A black streak or spot under the nail may signal subungual melanoma, a type of skin cancer. Melanoma often presents as a single dark stripe running vertically down the nail, which may spread to the surrounding skin. While uncommon, melanoma can affect anyone. However, those who experience excessive sun exposure or have a family history of skin cancer may be at higher risk.

How to Treat Black Toenails

Some cases of black toenails may resolve with time and care, but others require medical intervention. Here’s how to get rid of black toenails:

1. Rest: Rest may suffice if you stubbed your toe or wore tight shoes for a short period. Healing can take a few days or weeks, depending on the severity. Seek medical attention if you experience increased pain, swelling or changes in toenail color.
2. Drainage procedures: If the trauma is more severe and has caused significant pain or pressure, you may need to consult a podiatrist. Podiatrists can perform a drainage procedure, which involves puncturing a small hole in the nail to release trapped blood.
3. Antifungal treatments: When the condition results from a fungal infection, the treatment requires addressing the source of the black toenail fungus. Antifungal prescription-strength solutions can target fungi on and around the nail. Practitioners may also prescribe oral medication to address the infection from within your body. Fungal infections can take weeks to months to heal as new, healthy nail growth gradually replaces the infected nail.
4. Correcting ingrown toenails: If your black toenail results from an ingrown toenail and infection, targeted treatments will address the nail and the surrounding skin. A podiatrist can trim or remove the ingrown portion of the nail and treat the infection. They may also explore and determine better treatment options or suggest a surgical procedure, if necessary.
5. Addressing underlying health conditions: If the condition stems from diabetes, poor circulation or vitamin deficiencies, treating the root cause is crucial. Consult your health practitioner to discuss proper medication, diet and exercise to manage the condition.

How to Prevent Black Toenails

You can avoid black toenails with simple habits that protect your feet from trauma and infection. Here’s how to keep your toenails healthy:

• Choose the right shoes: Ill-fitting shoes can pressure your toes, leading to bruising, ingrown toenails or fungal infections. Look for shoes that give your toes room to move. Athletes should invest in sport-specific shoes that absorb impact and prevent toenail trauma.
• Trim your toenails properly: Cut your toenails straight across, avoiding rounded edges. Use clean, sharp clippers to prevent jagged edges, splitting or infections.
• Keep your feet dry and clean: Wash your feet thoroughly and dry them completely. Choose socks made from breathable materials that wick sweat away from the skin.
• Avoid walking barefoot in public areas: Wear flip-flops or shower shoes in pools or gym showers to create a barrier between your feet and the floor. If you frequent these areas, disinfect your shoes regularly and avoid sharing footwear or towels.
• Maintain good blood circulation: Gently stretch your toes and feet to promote blood flow. If you’re diabetic, manage your blood sugar levels and schedule foot checks.
• Monitor your activity levels: Gradually increase activity intensity to avoid sudden strain. Ensure your shoes can cater to your activity and offer ample cushioning.
• Schedule regular foot exams: Foot exams with a podiatrist can help catch problems early and address underlying conditions.

Contact Foot & Ankle Surgical Associates to Treat Black Toenails

Foot & Ankle Surgical Associates can help you address black toenails. Our experienced podiatrists specialize in diagnosing and treating various foot conditions. With a patient-centered approach, we ensure you receive personalized care tailored to your needs. Our team takes the time to identify the root cause of your concern and create a treatment plan that works best for you.

We use state-of-the-art diagnostic tools to provide noninvasive solutions and recommend surgical procedures only when necessary. We’ll also provide the knowledge and tools to prevent future toenail issues. Book your consultation or call our office for your toenail treatment today.

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