A black toenail can be caused by several factors, including trauma, fungal infections, or underlying medical conditions. Here are some possible causes:
- Trauma: Black toenails are often caused by trauma or injury to the nail, such as from stubbing your toe, dropping something heavy on your foot, or from repetitive activities such as running or hiking. This can cause bleeding under the nail, which can turn the nail black.
- Fungal infection: Fungal infections can also cause toenails to turn black. Fungal nail infections typically cause the nail to thicken, become brittle, and change colour. In some cases, the nail may turn black or dark brown.
- Bacterial infection: In some cases, a bacterial infection can cause a black toenail. Bacteria can enter the nail bed through a cut or break in the skin, causing an infection that can turn the nail black.
- Underlying medical conditions: Certain medical conditions, such as diabetes or peripheral artery disease, can cause changes in the nails, including discolouration.
If you have a black toenail and are unsure of the cause, it’s best to see a healthcare professional for a proper diagnosis and treatment. In some cases, a black toenail may need to be removed to prevent further complications.