Black Color Nails – Causes, Symptoms, and Treatment

The appearance of black color nails can be alarming and sometimes indicates an underlying health issue. 

Causes of Black Color Nails

Trauma and Injury:

Subungual Hematoma: One of the most common causes of black nails is trauma or injury, resulting in a collection of blood under the nail (subungual hematoma). This can occur from dropping something heavy on the toe or finger or from repetitive trauma, such as running or ill-fitting shoes.

Symptoms: Intense pain, pressure, and discoloration (black or dark red) under the nail.

Fungal Infections:

Onychomycosis: Certain fungal infections can cause the nail to turn black, particularly if the infection is severe or has been left untreated for a long time.

Symptoms: Thickening of the nail, brittle or crumbly texture, and black or dark discoloration.

Bacterial Infections:

Pseudomonas Infection: The bacterium Pseudomonas can infect the nail bed, causing a greenish-black discoloration.

Symptoms: Green-black discoloration, possible nail detachment, and a foul odor.

Melanonychia:

Melanin Pigmentation: This condition involves the increased production of melanin (the pigment that gives skin and hair its color) in the nail bed. It can cause black or brown streaks in the nails.

Symptoms: Longitudinal black or brown lines or streaks on the nail.

Nail Melanoma:

Subungual Melanoma: A rare but serious form of skin cancer that develops under the nail, often presenting as a dark streak.

Symptoms: A new dark streak that appears suddenly, changes in an existing streak, nail dystrophy, or a dark band extending to the surrounding skin (Hutchinson’s sign).

Underlying Medical Conditions:

Anemia: Severe anemia can cause changes in nail color, including blackening.

Kidney Disease: Certain kidney disorders can lead to nail discoloration.

Symptoms: Varies depending on the condition, but may include other systemic signs such as fatigue, swelling, and changes in urine output.

When to Seek Medical Advice

While not all black nail conditions are serious, it’s crucial to consult a healthcare professional if you experience any of the following:

Persistent pain or swelling.

A new or changing dark streak in the nail.

Signs of infection (redness, warmth, pus).

Black nails without a clear cause or after minor trauma.

Associated systemic symptoms (fever, fatigue, changes in other parts of the body).

Treatment and Management

Trauma-Related Black Nails:

Subungual Hematoma: Minor cases often resolve on their own as the nail grows out. For severe pain or pressure, a healthcare provider may need to drain the blood under the nail.

Protection: Wear protective footwear and avoid repetitive trauma.

Fungal and Bacterial Infections:

Antifungal Treatments: Topical or oral antifungal medications can be prescribed for fungal infections.

Antibiotics: Bacterial infections may require topical or oral antibiotics.