What illness causes pain inside the big toenail?

Pain inside the big toenail may be caused by conditions such as athlete's foot, paronychia, or neuritis. It is recommended to seek medical attention at a hospital to determine the exact underlying cause of the symptoms.

1. Athlete's Foot

Infection with fungi such as Trichophyton mentagrophytes, Trichophyton rubrum, or Epidermophyton floccosum can lead to athlete’s foot, affecting areas like the sole, heel, and spaces between the toes. This causes skin lesions and peeling. Some patients may also experience bleeding and pain, which can result in pain inside the big toenail.

2. Paronychia

Paronychia is usually caused by bacterial infections, commonly Staphylococcus aureus, due to factors such as pulling out ingrown splinters near the nail fold, excessive trimming of nails, or ingrown toenails. It typically leads to redness, swelling, warmth, and pain at the junction between the nail plate and the surrounding skin folds, resulting in pain beneath the big toenail.

3. Neuritis

Neuritis around the big toenail may occur due to external pressure or compression on the big toe, or as a result of viral or bacterial infections. This can cause pain, numbness, and redness inside or around the big toenail.