How Toenail Fungus Looks When It’s Dying

Fungal nail infections (onychomycosis) can be difficult to treat but can be helped by treatments such as oral and topical antifungal medications. The infection is considered cured when new nail growth is healthy as the nail affected by fungal infection grows out.

This article will discuss how toenails with a fungal infection look compared to healthy ones, what treatments are available, how to support healing at home, and what happens when toenail fungal infections recur or won't go away.

Illustration by Julie Bang for Verywell Health

To determine if the toenail fungus is dying, look at the base of the nail. When the new growth from the base is healthy, the infection is considered clinically cured.

If necessary, mycological (a branch of biology that deals with fungus) cure can be determined with a negative potassium hydroxide (KOH) preparation (the sample is examined under a microscope) and negative fungal culture (a sample is given time to grow to see if fungus is present).

Treatments that may be used for toenail fungal infection include:

Natural remedies, such as tea tree oil, have not been well-studied for efficacy in treating toenail fungal infection.

Toenails that have a fungal infection typically become discolored. They often start with a white spot, and can turn yellow, green, or brown.

Infected toenails may also:

Once the infection is successfully treated, new growth of healthy nail will occur from the base of the nail. New nail cells push out old nail cells. A healthy toenail looks like a healthy fingernail, with a pinkish color from the tiny blood vessels on which the nail bed sits.

It takes about 12 to 18 months for toenails to be completely replaced by new growth.

Toenail fungal infections can be difficult to treat. Medications are effective against the fungal infection in about 50% of those who use them, and the infection can return.

Depending on the extent of your infection and medical conditions you may have, your healthcare provider may start with topical treatment, which carries less risk.

If topical treatments don't work, your healthcare provider may suggest oral medications, if the benefits of this treatment outweigh the risks, such as potential damage to the liver. Oral medications tend to be more effective than topical.

To help prevent toenail fungal infections, try measures such as the following:

Nail polish and artificial nails will not get rid of a nail infection.

The relapse rate for toenail fungus infection is up to 53%.

Infection is more likely to return in people who have conditions such as diabetes. Untreated, the infection can spread to other areas such as other nails. Fungal skin infections are also associated with fungal nail infections. It's important to talk to your healthcare provider if you suspect you have a skin infection or that your fungal infection has returned.

If recurrence of toenail fungal infection is a concern, your healthcare provider may suggest removing the nail and using chemicals to destroy the nail matrix. This prevents the nail from growing back.

Contact your healthcare provider or seek immediate medical care if you have:

It is important for people who have diabetes and those with a weakened immune system to treat toenail fungal infections promptly to avoid possible complications, such as:

If you have diabetes or a weakened immune system, see your healthcare provider at the first sign of a toenail fungal infection.

Toenails that have a fungal infection can be discolored, brittle, and thickened, while healthy toenails are clear and pinkish. The infection is considered cured when a healthy nail is growing from the base of the nail. To help prevent toenail fungal infection, take measures such as keeping your feet cool and dry, wearing footwear in public places, and trimming your toenails.

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By Heather JonesHeather M. Jones is a freelance writer with a strong focus on health, parenting, disability,and feminism.