What are ingrown toenails? Causes, symptoms, diagnosis, treatment, complications, and prevention

If the edge of the nail of your big toe has grown into the skin and cut through, you have an ingrown toenail. We also call it onychocryptosis. Ingrown toenails cause swelling, redness, pain, and sometimes infections.

Causes of ingrown toenails

There are several possible causes. In many cases, they are the result of improper toenail trimming, i.e., you did not cut your toenails properly. If you cut the sides of the nail too short, you may increase your risk of subsequently having an ingrown toenail.

Here is a list of the most common causes:

  • Improper trimming of nails.
  • An injury, such as somebody stepping on your toe or accidentally kicking into something.
  • Nail infections. The UK’s National Health Service (NHS) says that a fungal nail infection can cause your toenail to thicken or widen.
  • Sweaty feet.
  • If you have naturally curved toenails, your risk of onychocryptosis is greater than average.
  • Some people with underlying conditions such as diabetes are prone to ingrown toenails and related infections.

Signs and symptoms

A painful toe is a symptom while a swollen toe is a sign. Why? If only the patient can feel, detect, or sense something, it is a symptom. If the patient and other people can see or detect something, it is a sign. A doctor needs to ask you whether your toe hurts, but they do not need to ask whether it is swollen.

The most common signs and symptoms of ingrown toenails are:

  • Pain and tenderness.
  • Redness around the affected area.
  • Swelling of the toe and/or around the nail.
  • There may be white or yellow pus if there is an infection.

Diagnosis of ingrown toenails

The patient, family member, friend, or medical professional can make an accurate diagnosis by looking at the affected toe. In most cases, no tests are required.

According to healthnavigator.org.nz:

“Your doctor will ask you questions about your symptoms and examine your toe to see if it is infected. Usually, no tests are needed to diagnose an ingrown toenail, other than a possible swab test.”

However, if the toe is very infected, the doctor may order an X-ray to determine how deep the nail has dug into the skin and see whether it has caused an injury. In rare cases, if the infection looks severe, they may take a sample culture to identify the type of infection.

The doctor may refer the patient to a specialist (podiatrist) for further treatment if there is a severe infection or the condition is recurrent.

Ingrown Toenails - Three images with information for non-professionals

Created by MedicalVocab.com using Wikipedia Commons images.


Treatment options depend on how severe the ingrown toenail is.

Home remedies

If there is no infection, the following home remedies can help:

  • Soak your foot in warm water. Do this a few times a day.
  • Place a piece of cotton or dental floss under the ingrown edge. This helps the nail to grow above the skin edge.
  • OTC pain relievers can help ease the pain. OTC stands for over the counter. We can buy over-the-counter medication without a doctor’s prescription. OTC drugs contrast with prescription drugs.

Infections or recurrences

If there is an infection or the problem keeps coming back, you will need to see a healthcare professional. If you are not sure whether to see one, phone/e-mail your doctor or, if you are in a pharmacy, ask the pharmacist in charge.

The specialist may recommend minor surgery to remove part of the toenail (or all of it).

You will also be given a prescription for antibiotics. Make sure you complete the course.

Complications of ingrown toenails

If your ingrown toenail is left untreated, the following complications are possible:

  • The infection may spread to the underlying bone, which can become serious.
  • A toe infection can lead to foot ulcers and open sores.
  • In some cases, there could be a loss of blood flow to the infected area.
  • People with diabetes or poor circulation are at a much higher risk of complications than the rest of the population.

Healthline.com says the following about people with a genetic predisposition:

“If you have a genetic predisposition to ingrown toenails, they may keep coming back or appear on multiple toes at once. Your quality of life may be affected by pain, infections, and other painful foot issues that require multiple treatments or surgeries. In this case, your doctor may recommend a partial or full matrixectomy to remove the toenails causing chronic pain.”


The following measures should reduce your risk of developing onychocryptosis:

  • Cut your toenails straight across – not rounded.
  • Do not cut your toenails too short.
  • Make sure that your shoes and socks fit well (avoid tight-fitting ones).
  • If your toenails are abnormally thick or curved, you may need surgery.
  • Check your feet daily for signs of any foot problems if you have diabetes.
  • If you work in hazardous conditions, wear steel-toe boots. (See quotation below)

The Cleveland Clinic says:

“Avoid trauma to the toe area. If you run, play soccer or participate in other sports where your toes get a lot of action, try to go barefoot for an hour or two afterward.”