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. A number of diseases, including psoriasis or fungal infections — also known as onychomycosis — can cause your toenails to grow thicker over time.

Other conditions like congenital disorders or chronic illnesses can also cause toenails to thicken.

Left untreated, thick toenails can become painful. Prompt treatment is key to resolving thick toenails. It’s important to note that fungal infections are difficult to cure and may require months of treatment.

Click here for a gallery of nail disorder images.

Around 1–8% of the population has a diagnosis of onychomycosis. Its occurrence is steadily growing. 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

Learn more about what your nail bed and nail plate are.

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

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

The images below show how toenails may be affected by fungal infection (onychomycosis).

A change in toenail thickness may be just one symptom of a fungal infection.

Other nail fungus symptoms include:

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

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

You might be likely to get toenail fungus from:

  • being barefoot in public places with wet floors, such as swimming pools, showers, and gyms
  • nail salon services like manicures and pedicures
  • 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 talk with a healthcare professional as soon as possible to receive an accurate diagnosis and to begin treatment.

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

The doctor will typically look at your nails to diagnose the condition. If needed, they may refer you to a dermatologist.

Dermatologists are doctors who specialize in skin, hair, and nail conditions. They often use a dermatoscope (handheld instrument) to look at nail changes. They may also take a swab from 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 does not contribute to secondary infections or complications.

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

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

Home treatments

While prescription treatments like topical and oral medications are highly effective, there are several options you can try at home to consider.

It’s important to talk with a doctor or healthcare professional if your toenails have become thicker or if you think you have toenail fungus.

Here are a few home remedies for toenail fungus:

  • 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 clear.
  • Apply tea tree oil twice a day every day.

Treating toenails for fungus may require you to stick to the treatment plan for several months. Toenails grow slowly. They can take 12–18 months to grow out, according to the American Academy of Dermatology.

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, and use a powder like Zeasorb powder to keep your feet dry.
  • 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 and keep your toenails trimmed short.
  • Make sure to use disinfected tools when trimming your nails.
  • Purchase new footwear if your nail fungus has recently been cured.

How do I get rid of thick toenails?

Keeping your toenails clean and moisturized can help. Home remedies like Vicks VapoRub and creams made with urea or tea tree oil may help. Talk with a healthcare professional. There are also medical treatment options available.

What will dissolve thick toenails?

Topical home remedies, like Vicks VapoRub, urea creams, and tea tree oil may help. Medical treatment options include oral and topical prescription medications, laser treatments, and nail removal.

What kills toenail fungus overnight?

There currently isn’t an immediate or overnight cure for toenail fungus. Common treatment options include topical treatments, oral medications, and surgical removal. However, even with surgical removal treatments, it may take 12 to 18 months for your toenails to return to their pre-fungus appearance.

Can I thin my thick toenails at home?

Sometimes, thick toenails are caused by injury to the nail bed, and you can file them thinner. If thick nails are caused by a fungus, you’ll need treatment options to help them grow thinner.

What does Vicks VapoRub do for toenails?

Thickened toenails are often caused by a fungal infection. Vicks VapoRub may help kill the nail fungus, relieving the infection and helping your toenails return to their typical thickness.

Toenails that grow thicker over time may indicate a fungal infection. 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.