What is the White Stuff Growing Under My Toenail?

Toenail growth abnormalities can occur for a variety of reasons, ranging from minor injuries to underlying medical conditions. Two of the most common causes of abnormal toenail growth are nail psoriasis and nail fungus. Both conditions can cause the toenails to become thickened, discolored, and brittle, which can be unsightly and uncomfortable. In this article, we’ll discuss nail psoriasis and nail fungus, including their causes, symptoms, and treatments.

Nail Psoriasis

Psoriasis is a chronic autoimmune condition that affects the skin and nails. When psoriasis affects the nails, it can cause pitting, ridges, and discoloration. In severe cases, it can also cause the nail to become thickened and disfigured. Nail psoriasis affects up to 50% of people with psoriasis and can be very difficult to treat.


The exact cause of nail psoriasis is unknown, but it is believed to be related to an overactive immune system. In people with psoriasis, the immune system attacks healthy skin cells, causing inflammation and the formation of scaly patches. When this happens in the nails, it can cause the cells in the nail bed to grow too quickly, leading to thickening and deformation of the nail. Common risk factors for nail psoriasis include:

  • Family history: People with a family history of psoriasis are more likely to develop nail psoriasis.
  • Smoking: Smoking can increase the risk of developing psoriasis and may worsen symptoms.
  • Stress: Stress can trigger psoriasis flare-ups, including nail psoriasis.
  • Infection: Infections, such as strep throat or skin infections, can trigger psoriasis.
  • Medications: Certain medications, such as lithium or beta-blockers, can trigger or worsen psoriasis symptoms.


Nail psoriasis can cause a variety of symptoms, including:

  • Pitting: Small depressions or pits in the nail surface.
  • Ridging: Vertical lines or ridges on the nail surface.
  • Discoloration: The nail may become yellow, brown, or greenish.
  • Thickening: The nail may become thicker than usual.
  • Separation: The nail may separate from the nail bed.
  • Crumbling: The nail may become brittle and prone to breaking.
  • Deformation: The toenail may become misshapen, curved, or distorted.


There’s no cure for nail psoriasis, but there are treatments that can help manage the symptoms. These include:

  • Topical medications: Creams and ointments containing corticosteroids or vitamin D analogs can help reduce inflammation and slow down the growth of skin cells in the nails. We commonly use urea products to help thin the nail plate and that can make the nails easier to cut as well. 
  • Systemic medications: In severe cases, oral or injected medications may be prescribed to suppress the immune system and reduce inflammation.
  • Light therapy: Exposure to ultraviolet light can help reduce inflammation and improve the appearance of the nails.
  • Nail surgery: In very severe cases, surgery may be necessary to remove the affected nail.

Nail Fungus


Nail fungus is caused by the overgrowth of fungi, such as dermatophytes, yeasts, and molds, that can infect the toenail bed and cause damage to the nail plate. Fungi thrive in warm and moist environments and can easily invade the nails if they come into contact with contaminated surfaces or objects. Common risk factors for nail fungus include:

  • Age: As we age, our nails become more brittle and prone to cracking, which can create an entry point for fungi.
  •  Preexisting conditions: Preexisting conditions such as athlete’s foot can migrate into the nails easily. 
  • Gender: Men are more likely to develop nail fungus than women.
  • Diabetes: People with diabetes are more susceptible to infections, including nail fungus.
  • Immune system disorders: People with weakened immune systems, such as those with HIV or undergoing chemotherapy, are more susceptible to nail fungus.
  • Poor circulation: People with circulation problems, such as peripheral artery disease, may be more susceptible to nail fungus.


Nail fungus can cause a variety of symptoms, including:

  • Thickening: The toenail may become thicker than usual, making it difficult to trim or cut.
  • Discoloration: The toenail may become yellow, brown, or white in color.
  • Brittleness: The toenail may become brittle and prone to cracking or breaking.
  • Separation: The toenail may separate from the nail bed, causing pain and discomfort.
  • Deformation: The toenail may become misshapen, curved, or distorted.

In some cases, nail fungus may also cause a foul odor or discharge from the affected toenail.


Nail fungus can be challenging to treat, and in some cases, it may not be possible to fully cure the infection. However, there are several treatment options available that can help manage the symptoms and prevent the infection from spreading. These include:

  • Antifungal medications: Oral or topical antifungal medications can be used to kill the fungi that cause nail fungus. These medications may need to be taken for several months to be effective, and they may have side effects, such as liver damage or gastrointestinal upset.
  • Topical solutions: There are several over-the-counter topical solutions available that can be used to treat nail fungus. These solutions usually contain an antifungal agent and need to be applied to the affected toenail regularly for several months.
  • Nail removal: In severe cases, nail removal may be necessary to treat nail fungus. This can be done surgically or with a chemical treatment that dissolves the nail.


Preventing nail fungus can be challenging, but there are several steps you can take to reduce your risk of infection. These include:

  • Keep your feet clean and dry: Wash your feet daily and dry them thoroughly, especially between the toes.
  •  Wear moisture-wicking socks: Moisture-wicking socks will help keep sweaty feet dry.
  • Wear shoes that fit well: Shoes that are too tight or too loose can cause pressure on the toenails, making them more susceptible to damage.
  • Use antifungal sprays or powders: Sprays or powders can be used to reduce the risk of fungal infections in shoes and socks.

Contact Gurnee Podiatry & Sports Medicine Associates Today!

In conclusion, abnormal toenail growth can be caused by various conditions, including nail psoriasis and nail fungus. While they have different causes and symptoms, both conditions can cause thickened, discolored, and deformed toenails. It is essential to seek medical attention if you’re experiencing abnormal toenail growth to determine the underlying cause and receive proper treatment. Schedule your appointment online to see Dr. Bever or Dr. Schoene for an evaluation of your nail concerns.