What Causes Blackened Toenails

What Causes Blackened Toenails?

Blackened toenails can be a cause of concern for many people. They can be unsightly and may cause discomfort or pain. There are various factors that can contribute to the discoloration of toenails, ranging from minor injuries to underlying medical conditions. Understanding the possible causes can help in identifying the appropriate treatment or preventive measures.

1. Trauma or Injury

One common cause of blackened toenails is trauma or injury. Stubbing your toe or dropping something heavy on it can lead to bleeding under the nail, known as subungual hematoma. The blood trapped underneath the nail causes discoloration, turning the nail black or dark purple. The nail might also become tender or painful due to the pressure from the blood.

2. Infection

Infections, such as fungal infections or bacterial infections, can also cause blackened toenails. Fungal infections, like onychomycosis, can lead to nail discoloration, thickening, and crumbling. Bacterial infections, such as paronychia, can cause inflammation and pus-filled blisters on the skin around the nail, leading to discoloration and pain.

3. Medications

Certain medications, such as chemotherapy drugs or antibiotics, can cause blackening or discoloration of the toenails as a side effect. This is often temporary and may resolve once the medication is discontinued. However, it is important to consult with a healthcare professional if you suspect any medication-related changes in your nails.

4. Poor Footwear

Wearing ill-fitting or tight shoes can put pressure on the toenails, leading to discoloration over time. Constant friction and pressure can cause blood vessels under the nail to rupture, resulting in a blackened appearance. Additionally, shoes that do not provide proper ventilation can create a moist environment ideal for fungal infections, which can also contribute to blackened toenails.

5. Subungual Melanoma

In rare cases, blackened toenails can be a sign of a serious condition known as subungual melanoma, which is a type of skin cancer that affects the nails. It is important to mention that subungual melanoma is rare, but if you notice changes in your nails, such as vertical black lines, irregular borders, or enlargement of the nail, it is crucial to seek medical attention.

6. Nutritional Deficiencies

Certain nutritional deficiencies, such as iron deficiency or vitamin B12 deficiency, can lead to changes in the color and texture of the nails. Iron deficiency anemia can cause the nails to become brittle, thin, and concave, with a tendency to develop dark spots or lines. Vitamin B12 deficiency can lead to pale or yellowish nails that may also become dark or blackened.

7. Smoking

Smoking tobacco can have detrimental effects on overall health, including the nails. The toxins and chemicals in tobacco smoke can hinder blood flow and oxygen delivery, leading to nail discoloration and poor nail health. Smokers may be more prone to developing blackened toenails due to compromised blood circulation.

8. Age

As we age, the nails may naturally become more prone to discoloration. This can be attributed to various factors, such as decreased blood flow, diminished nail growth, thinning of the nail plate, and increased exposure to environmental factors over time. While age-related changes may not necessarily cause blackened toenails on their own, they can contribute to the development of other underlying causes.

9. Medical Conditions

Certain medical conditions, such as diabetes or peripheral artery disease, can affect blood circulation to the extremities, including the toes. Poor blood flow can make the nails more susceptible to injuries, infections, and discoloration. Additionally, medical conditions that affect the immune system, such as psoriasis or lupus, can also cause changes in the nails, including blackening or discoloration.

10. Genetics

Genetics can also play a role in the tendency to develop blackened toenails. Some individuals may be more prone to certain nail conditions or abnormalities due to their genetic makeup. If you have a family history of blackened toenails or related nail conditions, it is important to be mindful and take preventative measures accordingly.


Q1. Are blackened toenails painful?

A1. Blackened toenails can be painful, especially if they are caused by trauma or infection. The pressure exerted by the accumulated blood or the presence of inflammation can cause discomfort.

Q2. How long does it take for a blackened toenail to heal?

A2. The healing process for a blackened toenail can vary depending on the underlying cause and severity of the injury or infection. It can take several weeks or even months for the nail to fully heal and the discoloration to fade.

Q3. Can I treat blackened toenails at home?

A3. Treatment options for blackened toenails depend on the underlying cause. In some cases, home remedies such as warm soaks, proper nail care, and wearing comfortable shoes can help alleviate symptoms. However, it is always advisable to consult a healthcare professional for an accurate diagnosis and appropriate treatment.

Q4. Can I prevent blackened toenails?

A4. While not all cases of blackened toenails can be prevented, there are steps you can take to reduce the risk. This includes wearing properly fitting shoes, maintaining good foot hygiene, avoiding excessive trauma or injuries, and addressing any underlying medical conditions that may contribute to nail discoloration.

Q5. Should I see a doctor for blackened toenails?

A5. It is recommended to consult a healthcare professional if you notice persistent or concerning changes in the color or texture of your toenails. They can help determine the underlying cause and provide appropriate treatment or further evaluation if needed.

Q6. Can blackened toenails be a sign of cancer?

A6. While blackened toenails can be a sign of subungual melanoma, it is a rare occurrence. However, if you notice any suspicious changes in your nails, such as rapid or progressive discoloration, irregularities in shape or texture, or accompanying symptoms, it is important to seek medical attention for proper evaluation and diagnosis.

Q7. Can I wear nail polish on blackened toenails?

A7. It is generally advisable to avoid wearing nail polish on blackened toenails, especially if the cause is injury or infection. Nail polish can potentially trap moisture and exacerbate the condition. It is best to allow the nails to breathe and heal properly.

Q8. Can blackened toenails be a sign of a fungal infection?

A8. Yes, blackened toenails can be a sign of a fungal infection, such as onychomycosis. Other symptoms may include thickening, crumbling, or distorted nail shape. It is important to consult a healthcare professional for an accurate diagnosis and appropriate treatment.

Q9. Can nutritional supplements help with blackened toenails?

A9. Nutritional supplements may be beneficial for addressing underlying nutritional deficiencies that may contribute to blackened toenails. However, it is important to consult with a healthcare professional before starting any supplements to ensure it is appropriate for your specific situation.

Q10. Can blackened toenails be prevented during sports or physical activities?

A10. While injuries can sometimes be unavoidable, wearing appropriate footwear, such as well-cushioned and supportive athletic shoes, can help reduce the risk of trauma to the toenails during sports or physical activities. Proper warm-up exercises and adequate rest periods can also contribute to the overall health and resilience of the nails.


Blackened toenails can have several causes, ranging from trauma and infections to underlying medical conditions or lifestyle factors. Understanding the potential causes can help in identifying the appropriate steps for prevention, treatment, or seeking medical attention when necessary. It is always advisable to consult with a healthcare professional for an accurate diagnosis and individualized guidance based on your specific situation.

Rate article
( No ratings yet )