Ingrown toenails

What is an ingrown toenail, and how common is it?

An ingrown toenail (onychocryptosis) happens when the side of a nail curls down and grows into the skin around it, which can make the toe painful, red and swollen¹. It usually affects the big toe, though other toes can be involved².

It's common: about 20% of foot problems seen in primary care are ingrown toenails³. It can happen at any age, but teenagers are most prone⁴.

A nail that curls into the skin without piercing it isn't a true ingrown toenail, but it can still be sore and look red and inflamed². It's worth keeping an eye on.

What causes an ingrown toenail, and who gets it?

Cutting nails the wrong way is the most common cause: too short, or not straight across⁵. Other things add to the risk: tight shoes, socks or tights; a knock to the toe; picking or tearing at the corners; sweaty feet; and naturally curved or fan-shaped nails¹. Nails that arch upwards in the middle are more likely to press into the side of the toe⁶.

Repeated pressure from some sports (such as football, ballet or running) and foot shape problems such as bunions or hammer toes can also play a part². Males are affected more often⁴.

If you have diabetes, an ingrown toenail matters more, because it can raise the risk of a foot ulcer⁷.

What does it feel like, and how is it diagnosed?

Pain is the main symptom. It usually starts as minor discomfort and builds⁶. The toe may be red, swollen and tender, with hardened skin beside the nail, and symptoms usually get worse rather than better¹.

A podiatrist or doctor will ask about your symptoms and look at the toe. Some other problems, including a bone infection or a growth in the nail bed, can look similar⁴. A toe that doesn't look or behave like a typical ingrown toenail needs checking rather than assuming.

What helps first?

Simple home care is the usual first step for mild cases³. You can try:

• soaking your foot in warm water for 15–20 minutes, 3 or 4 times a day, then gently pushing the skin away from the nail corner with a cotton bud¹;
• wearing wide, comfortable shoes and cutting your nails straight across, not too short;
• leaving the nail alone: don't pick at it or try to remove it yourself¹.

In the early stages a podiatrist can fit a gutter splint (a small support that lifts the nail edge away from the skin)⁴. It isn't clear yet how well non-surgical care works compared with surgery⁵, so if home care isn't helping, see a podiatrist rather than carrying on alone.

What helps if that isn't enough?

Nail surgery under local anaesthetic may be recommended if the problem keeps coming back, isn't improving, or needs repeated courses of antibiotics². Surgery is better at preventing it coming back than gutter treatment, and probably better than a brace⁵.

A common approach removes the troublesome edge of the nail and treats the nail root so it doesn't regrow, though no one technique is ideal⁴.

Before surgery, tell the podiatrist if you've had any anaesthetic in the last 24 hours, and if you have epilepsy⁸.

How long does it take to settle, and how can I stop it coming back?

A first ingrown toenail is likely to settle, but slowly². In general they aren't expected to clear up without proper treatment⁵, so see a podiatrist early if it isn't improving or keeps coming back.

To help stop it returning:

• cut nails straight across, not too short and not at the edges⁹;
• avoid tight or ill-fitting shoes⁹;
• keep your feet clean and thoroughly dry⁹;
• don't pick or tear the corners¹.

Nails that arch upwards in the middle become more common with age, and a podiatrist can help you cut them⁶.