HealthInfo Waitaha Canterbury
An ingrown toenail (onychocryptosis) happens when part of your nail pierces the skin. This can often lead to infection.
How bad an ingrown toenail is can vary. Usually, the side of the nail penetrates (curves down) and it's difficult to see the edge of the nail. In some cases, the corner or a small spike of nail can penetrate the skin, which can result in an infection.
If an ingrown toenail is infected the toe will be red, inflamed and painful.
Lots of things can cause ingrown toenails:
Trimming or tearing down the sides of your toenail can cause an ingrown toenail. Leaving a sharp corner also puts pressure on your skin.
A curved nail is more likely to become an ingrown toenail than a flat one. The shape of your nails is usually inherited, but it can be influenced by trauma or shoe pressure.
Tight footwear is more likely to increase pressure between the nail and the skin in the nail fold.
Injury can change the shape of the nail.
Pressure from the toe next to the nail that is ingrown can be a cause.
If you have a plump toe or your feet swell, you're more prone to ingrown toenails.
Pain is the main symptom of an ingrown toenail. It usually starts as minor discomfort and increases to pain.
Your toe is not necessarily infected, but this can develop after the nail breaks the skin to become ingrown. The infection can spread, making the toe red and inflamed (paronychia). Pus may also develop, and large growths of skin can develop if the ingrown toenail is left for too long.
If your toe is swollen or painful, the redness has spread beyond your toe and into your foot or you're feeling unwell, you'll need urgent medical attention for Cellulitis.
Take the following steps to prevent ingrown toenails:
Other advice:
A podiatrist can help with an infected nail and in many cases can remove an ingrown toenail without surgery or too much pain. If needed, they will recommend minor surgery and, in some circumstances, refer you to your general practice team for medication. Many general practices can also help with infected nails and ingrown toenails.
If you have diabetes, it's important to get any foot problems treated quickly as sometimes seemingly minor things can progress to cause serious problems. If you have diabetes and there is any sign of infection (increasing redness, swelling, pus, pain or feeling unwell), seek medical attention urgently. If your doctor refers you to a podiatrist because you have diabetes, podiatry treatment could be publicly funded.
Written by Podiatry NZ. Adapted by HealthInfo clinical advisers. Last reviewed April 2023.
Review key: HICCA-28239