Toenail fungus can cause a thickening of the toenail, as well as other changes in appearance. This can lead to pain and discomfort, and should be treated promptly to prevent further issues.

Changes in your toenails may be a symptom of an underlying condition. Toenails that grow thicker over time likely indicate a fungal infection, also known as onychomycosis.

Left untreated, thick toenails can become painful. Prompt treatment can be key to curing the nail fungus. Fungal infections might be difficult to cure and may require months of treatment.

A change in the thickness of your toenails may be just one symptom of a fungal infection.

Other symptoms of nail fungus include:

  • toenails that change in color to yellow, brown, or green
  • a foul odor that comes from the toenail
  • toenails that can lift up from the nail bed
  • toenails that split or crumble
  • toenails that look scaly or chalky
  • toenails with dirt and other debris under them

You may notice no discomfort in the early stages of the infection. As symptoms build, your toenails may become painful.

Around 1 percent to 8 percent of the population has a diagnosis of onychomycosis, and its occurrence grows. This condition happens when a fungus or yeast enters your toenail:

  • where your toenail and nail bed meet
  • in a crack in your toenail
  • in a cut in your skin that touches your toenail

The fungus or yeast grows under the nail bed, where it’s moist. The infection is initially minor, but with time may spread and cause your toenail to grow thicker, which can lead to other symptoms.

Your toes can often be susceptible to fungal infections because of exposure to wet areas. Moisture helps fungus spread.

You might be likely to get toenail fungus from:

  • being barefoot in public places with wet floors, such as swimming pools, showers, and gyms
  • frequent or prolonged exposure to water
  • shoes that constrict your feet
  • sweaty feet and shoes
  • damage to a toenail
  • athlete’s foot that spreads to your toenails
  • medications that suppress your immune system
  • genetics
  • smoking

You might also be likely to get toenail fungus if you have a preexisting medical condition, such as:

Cancer treatments may increase the likelihood of developing nail fungus. If you have a preexisting condition and develop fungus, it’s very important to treat it as soon as possible.

Call a doctor if you notice a change in the appearance of your nails. Treating a fungal infection in its early stages may help prevent the condition from worsening.

Your doctor will typically look at your nails to diagnose the condition. The doctor may also take a swab underneath the nail or take a toenail clipping to diagnose the condition.

Untreated toenail infections can cause some complications. Over time, the infection can get worse, and symptoms may become more severe. Toenails might thicken to the point that they cause discomfort when you try to wear shoes, or even make it more difficult to walk.

If you have preexisting medical conditions, treatment can be vital so that the fungus doesn’t contribute to secondary infections or complications.

Although not all cases of toenail fungus need treatment, thick toenails may be a symptom of worsening fungus.

Several methods are available to treat your toenails. You can try some home-based treatments first and then talk with your doctor about prescription-based options. Topical and oral medications are the mainstays of therapy.

Home-based treatments

You can try a variety of home-based methods to treat nail fungus. However, it’s always a good idea to talk with your doctor before going straight to home remedies. You can try the following home remedies:

  • Clean the affected area with soap and water daily.
  • Groom your nails regularly. Soften your nails first by applying urea cream (Aluvea, Keralac) and wrapping your feet in bandages at night. Then, wash off the urea cream, and use a nail clipper and nail file to trim your nails.
  • Apply an over-the-counter fungal treatment after you gently file your nails.
  • Apply Vicks VapoRub on your toenail each day. This may help the infection subside.
  • Apply tea tree oil twice a day every day.

Medical treatments

Toenail fungus may require medical interventions that involve prescriptions and recommendations from your doctor. These include:

  • topical medications
  • oral medications
  • laser treatments
  • removal of the toenail to treat the nail bed

If you take oral medication prescriptions, you may need routine blood testing, as some of these medications can affect the liver.

Treating toenails for fungus may require you to stick to the treatment plan for several months. Toenails grow slowly, and they can take 12 to 18 months to grow out.

You may experience a recurrence of toenail fungus after treatment. Make sure to talk with your doctor if you experience chronic fungal infections

You can reduce the risk of thick toenails or the recurrence of toenail fungus in several ways:

  • Keep your feet clean by washing them with soap and water regularly. Dry them off with a towel afterward.
  • Keep your feet as dry as possible: Change your socks a few times a day, wear cotton socks that remove moisture from your feet, rotate your shoes so they can dry out, and purchase shoes that breathe and don’t constrict your feet.
  • Try a foot powder that keeps your feet dry.
  • Wear flip-flops or other shower shoes when you are in locker rooms or at the pool.
  • Groom your feet properly.
  • Make sure to use disinfected tools when trimming your nails.
  • Purchase new footwear if your nail fungus has recently been cured.

Toenails that grow thicker over time may indicate a fungal infection. The good news is that if an infection is diagnosed, prompt treatment can help cure it.

Additionally, there are simple ways to help lower your risk of toenail fungal infection, including wearing sandals or shoes in locker rooms, keeping your feet as dry as possible during the day, and practicing good foot hygiene.