Black spot under toenail

Black Toenails

When a body part is a different color than normal, it can be a clear indication that something is wrong. Such is the case with black toenails. In this condition, the soft tissue in your nailbed has either become bruised, started bleeding (subungual hematoma), or is possibly displaying a sign of cancer. Fortunately, most of the times cancer is not the cause of the dark discoloration, but it is still important to know when to come see Dallas Podiatry Works and receive the black toenail treatment you need.

Symptoms and Causes of Black Nails

The most apparent symptom of this particular condition is discoloration of the affected nails. Contrary to the name, black toenails can actually be a range of colors. These may appear to be reddish, brownish, greenish, or purplish, too. In addition to the color, you might experience pain, foul odor, or discharge coming out from under the nail.

There are a couple different causes of black toenails, including:

  • Physical trauma or injury. If you drop something heavy on your foot or stub your toe hard against a wall or curb, you could end up with a darkened toenail.
  • Repeated trauma. Instead of a single traumatic event like that above, you might develop a black nail from running or other athletic activities. This is especially prevalent in long distance runners and those who do a lot hill work in their training.
  • Ill-fitting footwear. Shoes that are too tight or too small can create many issues for your toes and feet. Black toenails happens to be one of them.
  • Fungal infection. Less common than the other causes, a serious case of toenail fungus will lead to darkened nails. This condition will not go away on its own, so you should come in for treatment if this is something you are experiencing.
  • Malignant melanoma. This is the rarest, yet most serious, cause of a black toenail. It is also a key reason for making sure that you seek diagnosis from a professional for this condition. Early detection is necessary for catching melanoma at its most treatable stages.

Preventing Darkened Toenails

There are a variety of steps you can take to decrease your risk of black toenails. While you might not be able to completely eliminate the risk altogether, you can find benefit from the following steps:

  • Keep your toenails short and trimmed straight across (not rounded).
  • Wear shoes that fit properly and offer a thumb’s width of space between the front and your longest toe.
  • Wear protective footwear if you work with heavy items that could be dropped.
  • Enlist help if you need to move heavy objects at home.
  • Keep your nails and feet dry and clean to avoid fungal infections.
  • Wear clean shoes and socks, and allow your footwear to dry out between uses.
  • Treat nail issues during their earliest possible stages.

Black Toenail Treatment

For minor cases of black toenails caused by trauma, you may simply need to wait it out until the bruise in the nailbed goes away. Even so, it is still a good idea to come in and have our experts check it out to ensure there is not a greater concern.

When treatment is necessary, we may need to drain out any pooled blood. The processes we can use to do so include removing a nail or creating a hole either by puncturing or burning the nail tissue. You can expect the hole to remain in the nail until new tissue has grown, which will happen in time. Early care is best to ensure that your toenail returns to its normal state and color.

Treatment for Black Toenails in Plano, TX

No matter the cause behind your black toenails, Dallas Podiatry Works has the expert foot doctors you need to provide an accurate diagnosis and create an effective treatment plan. Contact us today by calling us at 972.566.7474 or use our online form and schedule your appointment at either our Dallas or Plano, TX offices.

Thick Toenails

Written By: Chloe Wilson – BSc(Hons) Physiotherapy
Reviewed By: FPE Medical Review Board

Thick toenails are a common problem, particularly in the elderly population.

It can be tempting to ignore them, hoping that they will get better on their own, but they are usually an indication of an underlying problem.

The two most common causes of thickened toenails are fungal infections and a medical condition called psoriasis, so we will start by having an in-depth look at both of those, including the symptoms, diagnosis and treatment options for each one.

We will then go on to look at some of the other possible causes such as aging, injury, Paronychia, Yellow Nail Syndrome, Rams Horn and Diabetes and how to tell which one you have.

Fungal Nail Infection

Fungal nail infections are the most common cause of thick toenails, accounting for almost half of all nail-related problems. Around 10% of the population of the States suffer from toenail fungus infections.

Fungal infections typically affect the toenails but can in some instances affect the fingernails as well. The medical term for a fungal nail infection is onychomycosis or tinea unguium.

Fungal Nail Symptoms

Fungal nail infections usually develop first on the edge of the nail and gradually spread to the middle of the nail.

The nail gradually thickens and may become discoloured, usually yellow, white, brown or black.

Thickened toenails from fungal infections become more brittle as they thicken and small pieces may crumble or break off.

As the toenail fungus infection gets worse, pain and swelling may develop in the skin underneath and around the nail. The nail may lift up from the nail bed and there may be an unpleasant odor due to the infection.

What Causes Toenail Fungus?

Thick toenails from onychomycosis are usually due to Dermatophytes (most common in temperate western countries), Candida or Non Dermatophytic Molds (most commonly affecting people who live in hot, humid climates).

It is normal to have microscopic fungi on your skin but sometimes this can lead to infection. Thickened toenail fungus infections are typically caused by:

  • Nail Injury: damage to the nail allows the fungus to invade and infect the nail
  • Poor Foot Hygiene: failing to keep the feet clean and dry
  • Shoes: tight shoes, or ones that don’t allow your feet to breathe leading them to become hot and sweaty are the ideal breeding ground for fungi
  • Walking Barefoot: in areas prone to fungal infection such as swimming pools, public showers and gyms
  • Aging: infections most commonly affect people over the age of 60 as nails naturally thicken and grow slower, the blood supply diminishes and there is increased susceptibility to infection
  • Weakened Immune System: from illness or medication
  • Health Conditions: such as diabetes, circulatory problems and psoriasis

Toenail fungus infections can be highly contagious so it is important to take steps to prevent spreading the infection by keeping your feet clean, dry and covered.

Treating Fungal Nail Infections

Treatment for thick toenails from fungal infections may include:

  • Anti-fungal Medications: either in the form of tablets or a special paint that you apply directly to the nail. People usually need to continue with these for a number of months until symptoms completely resolve. Oral medications tend to be more effective
  • Nail Removal: Either done surgically or with chemicals. This gives direct access to the nailbed which aids healing
  • Laser Therapy: Using infrared radiation to produce heat which kills the fungi that causes thickened toenails
  • Natural Remedies: Tea tree oil is often used to treat fungal nail infections. Many people report finding it beneficial but there is limited research to support its use

Some cases of thick toenails from fungal infections can be left to heal naturally without any treatment, simply by following good foot hygiene methods. Your doctor may take a swab from under your nail or a toenail clipping and send it off for analysis to confirm the type of fungal infection before starting you on medication.

Prognosis & Prevention

It can take many months for painful, thick toenails from fungal infections to settle, and the recurrence rate is relatively high at between 10-50%. This makes prevention all the more important. Things you can do help reduce the risk of developing thickened toenails from fungal infections include:

  • Good Foot Hygiene: Keep feet clean and dry, and keep nails trimmed
  • Appropriate Footwear: Wear clean, cotton socks and good-fitting shoes that allow your feet to breathe
  • Avoid Going Barefoot: In public areas such as showers and swimming pools
  • Don’t Share: Use your own towels, footwear and nail clippers/scissors so as to prevent the spread of infections – if visiting a salon for a pedicure, ensure that all equipment is sterilised between uses

Nail Psoriasis

Psoriasis is a common skin condition that can also affect the nails, leading to thick nails with areas of pitting, ridging, or abnormal contour. Psoriasis of the nails is accompanied by skin psoriasis in approximately 95% of cases, with the classic feature of patches of red, crusty, flaky skin covered with silvery scales, typically on the elbows, knees and scalp and trunk.

Psoriasis is thought to be caused by a problem with the immune system which causes an increase in the production of skin cells.

Symptoms of Nail Psoriasis

Typical symptoms of thickened toenails caused by Psoriasis include:

  • Discolouration: Nails may turn yellow, green or brown and there may be a small red or white spot that looks like a drop of blood or oil underneath the nail
  • Appearance: There may be pitting in the nail which looks like small pinprick holes (caused by a loss in cells from the nails surface), ridges or grooves (that run across the nail rather than up and down) and you may develop thick toenails if there is an infection. White, chalky debris may also build up under the nail, known as subungual hyperkeratosis
  • Nail Lifting: In some cases, the toenail may lift up off, or separate from, the nail bed, starting from the tip and extending towards the root of the nail. This is known as onycholysis

Treatment for Nail Psoriasis

The best options for treating thick toenails from psorasis are:

  • Systemic Medication: If you have both skin and nail psoriasis you will be given medication that is for the whole body such as methotrexate
  • Phototherapy: UV light can be helpful in treating both skin and nail psoriasis
  • Nail Creams: to rub into and around the nail such as corticosteroid cream, vitamin D or antimetabolites
  • Injections: Corticosteroid injections under the nail – these can be more effective than creams and can be done every few months

Psoriasis is not contagious so you don’t need to worry about passing on an infection from thick toenails if they are caused by psoriasis, unless there is an accompanying fungal infection.

Other Causes of Thick Toenails

There are a number of other things that can cause thick toenails such as:

Paronychia is a nail disease caused by a bacterial infection at the side or base of the nail. It may develop suddenly or gradually.

With Paronychia, the skin around the nail is usually red, inflamed, hot and painful and there is gradual thickening and discoloration of the nails and pus around the nail.

Paronychia can affect the fingernails or toenails.


Foot problems are common in people with type 2 diabetes due to the poor circulation and nerve damage associated with the condition. The nails do not receive the necessary nutrients to grow properly which can lead to blackened, thickened toenails.

Good foot care is vital for anyone who suffers from Diabetes and if you notice anything unusual, even if it seems fairly minor, you should seek medical advice immediately.

Ram’s Horn

Ram’s Horn, aka onychogryphosis, is a condition most commonly seen in the elderly.

With onychogryphosis, overgrowth of the toenails leads to discoloured, deformed (typically curved), thickened toenails that gradually curl to resemble a ram’s horn.

Thick toenails from Ram’s Horn typically develop due to cell damage from wearing tight, ill-fitting shoes, decreased blood supply to the nail, trauma/injury (such as dropping something heavy on the foot), infection, poor foot hygiene and failure to regularly trim the toenails.

Onychogryphosis usually need to be treated by a podiatrist as the nails become too thick to cut with conventional scissors or clippers. The nail may need removing altogether using the chemical phenol or a carbon dioxide laser.

Toe Injury

Repetitive minor trauma or pressure on the nail can result in thickened toenails. This commonly affects athletes and runners or people who wear tight, ill-fitting shoes. Alternatively, a more major injury, such as stubbing your toe or dropping a heavy object onto the toe can lead to thick toenails, particularly if the nailbed is damaged.

Yellow Nail Syndrome

Yellow nail syndrome is a rare condition that causes thick, dicoloured toenails and fingernails. Nails become thick, yellow and excessively curved.

There may be accompanying swelling in the arms and legs (lymphedema), as well as respiratory problems such as bronchiectasis, persistent coughing and pleural effusion (fluid build-up around the lungs).


As we get older, nails grow slower but this can lead them to thickening due to the piling up of nail cells, known as onychocytes. Repeated pressure on the feet and reduced circulation can also lead to thick toenails in the ageing population.

What Else Can Help?

Here we have look at the most common causes of thick toenails. Whilst it can be tempting to ignore the problem, prompt medical advice should be sought to discover the underlying cause and to prevent the condition from deteriorating further.

If pain in your toes is more of a problem, visit the toe pain section to find out what might be going on.

  1. Foot Pain Guide
  2. Foot Symptoms
  3. Thick Toenails

Page Last Updated: 2019-11-14
Next Review Due: 2021-11-14

Every once in a while, you should take a good look at your toenails. You might joke about how your feet aren’t so pretty — especially if you’re a CrossFit junkie or get bruised nails from long-distance runs — but a less-than-desirable toenail appearance.

“Healthy nails have a plump, pink nail bed and pink nail plate with strong but thin nails,” says Dr. Dana Canuso, podatric surgeon and founder of Dr. Canuso Skincare for Feet.

Here’s a guide to what the color of your toenails means, and what you should do if they start looking funky.

If your toenail is…purple

ANGHIGetty Images

If your toenails are purple, this may be due to a subungual hematoma, or bruising under the nail bed. “Small blood vessels bleed underneath the nail staining it darker,” says Dr. Miguel Cunha, founder of the NYC-based Gotham Footcare. “This is caused by trauma to the nail, such as dropping a heavy object or severely stubbing it.”

When this type of bruising occurs, you have two options. The first is to do nothing and simply allow the healthy nail to grow back in and gradually replace the darkened nail over time. But this can take “several months to resolve, as the toe nails only grow a millimeter per month,” he says.

The second option is to have a doctor remove the nail. “This option is only necessary if the nail becomes painful, which can happen sometimes if the pressure of blood accumulating underneath the nail plate becomes abnormal and excessive,” he says.

Purple nails can also signify a circulation issue “that is causing the nail to receive less oxygen than it needs,” says Canuso. “Because the tissue may be not getting the blood it needs, there may be pain in the toe or nail.” To treat these symptoms, you must treat the cause of the circulatory issue, which usually means a trip to your doctor.

If your toenails are…yellow or brown

“Yellow or brown nails could be caused by a problem with the respiratory system or lymphatic system, although they occur most often due to complications of diabetes or even more commonly,,” says Canuso.

When caused by a fungal condition, the nail will also be thick and brittle. “This is caused when a microscopic fungus infects one or more nails. These microscopic organisms typically thrive in dark, warm, and moist environments,” Cunha says.

It can happen from wearing moist sneakers or wearing the same pair for too long. “The insides of shoes are a perfect environment to harbor fungal organisms. This condition often begins as an infection in the skin,,” he says. As the nail fungus penetrates deeper into the nail, it may cause the nail to discolor, thicken, and develop crumbling edges

Treatment of this condition depends largely on the severity of the infection, but your doctor can do a nail biopsy to figure out what to do next. That sounds kind of extreme in a world where the drugstore offers plenty of OTC remedies. But if you really want something that works—and you do, because nail fungus can take a long time to get rid of, even if you get the right treatment—you need to get a diagnosis to be sure you’re using the right product to solve the right problem.

“Medicated antifungal nail lacquer may be prescribed for a localized mild to moderate infection. Prescription oral antifungal medications may be prescribed for a more serious infection,” Cunha says. Laser nail treatment is an alternative to oral medication, in which the laser passes a light through the toenail to kill the fungus without causing damage to the nail or the surrounding tissues. Just be aware that laser treatments can hurt and they’re not as well proven as the other remedies.

If your toenail is…white or has white spots

Leukonychia, or white spots or lines on the nail, can indicate several conditions. “White lines can appear if there is recurring pressure or trauma to the nail — for instance, if a runner wears shoes that are too small and the toe continues to hit the top of the shoe,” Cunha says. White spots will form if the injury was not severe enough to break the blood vessel, which would lead to darkening.

Leukonychia can also stem from a zinc deficiency, says Canuso. If the nail is completely white, or there are white lines across the nail bed, it “can mean or a,” she says.

If the white spots are caused by injury, try taking a nail-fortifying vitamin like biotin to improve hair, skin, and nails — and of course, you should stop doing whatever traumatic activity you’ve been doing. “Be patient and simply allow the healthy nail to grow and gradually replace the white nail over time,” Cunha says. This can take several months to resolve, as toenails typically grow only about a millimeter each month.

If you are concerned you’re anemic, watch out for other symptoms such as fatigue or muscle weakness. “These could be symptoms of protein deficiency or anemia, and you should consult your physician,” Canuso says.

If your toenail is…all black

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“Nails that are completely black in color may have numerous causes, such as a B12 deficiency, kidney problems, or liver disease. But the most common reason for the discoloration is trauma,” says Canuso. Simply stubbing your toe can cause a bruise to form under the toenail, which in turn can turn your nail black. And many distance runners aren’t strangers to the surprise black toenail after a long run in shoes you thought fit well.

If this happens, you must wait for the entire nail to grow out before the discoloration is gone, which can take about six to nine months, she says. If you’re concerned about any of the above conditions, consult with a physician, but rest assured that these are relatively rare.

If your toenail isn’t black, but has a black stripe running across or down it, the most common cause is a condition called linear melanonychia. “This condition occurs when pigments in the nail known as melanocytes make excess pigment, causing the nail beds to darken,” Cunha says.

The weirdest recent report of a nail stripe we’ve heard is from Beijing Children’s Hospital, where an 8-year-old came in with a mysterious blue band running down her nail. When doctors inspected it further, they noticed there was a blue substance under the nail, not in it. After talking with the girl and her family, they discovered she’d been playing with blue slime. It’s unusual for an external pigment to be that far into the nail, but doctors credit the “non-Newtonian fluid properties” of slime for allowing the pigment to siphon up the nail. The authors remind doctors to ask (which means patients can volunteer) about the history of your activities and things you’ve touched in addition to doing the usual tests. Sounds simple, but it’s easy to rely on advanced diagnostics rather than a simple conversation to inform a diagnosis.

Isadora Baum Isadora Baum is a freelance writer, certified health coach, and author of 5-Minute Energy.

Types of Fungal Nail Infection

Topic Overview

There are four major types of fungal nail infection . They are named for the area where the fungal infection starts. Dermatophytes cause almost all fungal nail infections.

  • Distal subungual onychomycosis (DSO) is the most common type of fungal nail infection. It is caused by the same fungi that cause most cases of athlete’s foot (dermatophytes). DSO infects the skin under the end of the nail (nail bed) and in the nail. The infection starts at the end of the nail bed, and part of the nail often turns yellow or white. Pieces of skin and nail fragments (debris) build up under the nail. As the condition gets worse, the nail may crumble and split, and it may separate from the skin. A thickened nail and a large amount of debris under the nail may cause discomfort when wearing shoes. DSO can be a lifelong infection and hard to treat. Shoes that fit poorly may make the infection worse or, in some cases, even cause the infection.
  • White superficial onychomycosis (WSO), the second most common type of fungal nail infection. It can be easily treated. WSO affects the top layer of the nail, first forming white spots on the nail surface. Eventually the entire surface of the nail becomes covered with a crumbly, chalky powder. The nail does not thicken and does not separate from the skin.
  • Candida onychomycosis, or yeast infection of the nail, is uncommon but can affect the nail and the skin bordering the nail (nail folds). This type of fungal infection is more common in fingernails than toenails. It may involve all of the nails at the same time and can cause the nail to separate from the nail bed. It invades weakened areas of the nail, which may become discolored white, green, or brownish, with an odd shape. The nail may look thicker than normal, and there may be signs of infection (reddened, swollen, tender, or warm) in the skin next to the nail (nail fold). Unlike the other types of fungal nail infections, the infection may be painful.
  • Proximal subungual onychomycosis (PSO) is caused by dermatophytes. It is more common in people infected with the human immunodeficiency virus (HIV) . PSO infects the base of the nail (skin at the nail fold), often thickening the skin, which can separate from the nail. The base of the nail may appear white, and the nail opaque. The skin on top of the foot may become infected.

Fungal Nail Infections


Fungal nail infections are common infections of the fingernails or toenails that can cause the nail to become discolored, thick, and more likely to crack and break. Infections are more common in toenails than fingernails.1 The technical name for a fungal nail infection is “onychomycosis.”


Nails with a fungal infection are often:

  • Discolored (yellow, brown, or white)
  • Thick
  • Fragile or cracked

A fungal nail infection usually isn’t painful unless it becomes severe.

Some people who have fungal toenail infections also have a fungal skin infection on the foot, especially between the toes (commonly called “athlete’s foot”).

How does someone get a fungal nail infection?

Fungal nail infections can be caused by many different types of fungi (yeasts or molds) that live in the environment. Small cracks in your nail or the surrounding skin can allow these germs to enter your nail and cause an infection.

Who gets fungal nail infections?

Anyone can get a fungal nail infection. Some people may be more likely than others to get a fungal nail infection, including older adults and people who have the following conditions:2,3

  • A nail injury or nail surgery
  • Diabetes
  • A weakened immune system
  • Blood circulation problems
  • Athlete’s foot (ringworm on the foot)


  • Keep your hands and feet clean and dry.
  • Clip your fingernails and toenails short and keep them clean.
  • Don’t walk barefoot in areas like locker rooms or public showers.
  • Don’t share nail clippers with other people.
  • When visiting a nail salon, choose a salon that is clean and licensed by your state’s cosmetology board. Make sure the salon sterilizes its instruments (nail clippers, scissors, etc.) after each use, or, you can bring your own.


Your healthcare provider may diagnose a fungal nail infection by looking at the affected nail and asking questions about your symptoms. He or she may also take a nail clipping to look at under a microscope or send to a laboratory for a fungal culture.


Fungal nail infections can be difficult to cure, and they typically don’t go away without antifungal treatment. The best treatment for a fungal nail infection is usually prescription antifungal pills taken by mouth. In severe cases, a doctor might remove the nail completely. It can take several months to a year for the infection to go away.

Information for Healthcare Professionals

There are a total of four well-known and well-studied kinds of fungal toenail infection. Each is subtly different to the others, although it can be difficult differentiating between them. That’s why we’ve created this in-depth guide so that you can identify it quickly.

Some kinds of fungal toenail infection are more common than others. This is because they have an easier time spreading between an infected person and a non-infected person. Another reason is that the fungus itself can reproduce more quickly and spread faster among people.

Again, some of the types of fungal toenail infection are more severe than the other kinds. They differ in how they affect the nail and nail bed, and some of them are more painful. You have to treat these types of fungal toenail with different methods.

Before examining the different forms of fungal toenail infection, have you considered that your toes aren’t infected? That’s right: even though your nails may appear to have contracted fungus, there’s a good chance they haven’t.

Somewhere around half of all suspected infections are completely free of fungus.

Instead, a large portion of people has nail dystrophies. This common deformity has a similar appearance to fungal infection but is a genetic and non-catching condition. As such, the problem is purely cosmetic and doesn’t require treatment (unless it affects your confidence).

Onychomycosis is also easily confused with a number of other nail disorders, such as:

  • General bacterial infections, which can turn the nail a black or green color
  • Psoriasis, eczema, and dermatitis, which can all affect fingernails and toenails
  • Mold or lichen, which can affect the nails (although rarely)
  • Onycholysis and onychogryphosis, both conditions of the nail with similar symptoms, but different causes

The American Academy of Dermatology recommends consulting a podiatrist before any treatment for your fungal toenails. This is because the oils, ointments, and creams used to get rid of fungus can have side effects. This is particularly true of oral treatments, which are commonly prescribed by podiatrists and dermatologists.

Of course, a large proportion of people will experience a fungal nail infection in their lifetime. So if you do suspect that you have an infection, ask your doctor for a diagnosis. But before you go and do that, take a look at our guide for the most common symptoms.

At the very beginning of a fungal toenail infection, there are no visible symptoms. But as the infection progresses, some signs should make your condition obvious. The symptoms that are common among almost all infections are as follows:

  • Discoloration of your toenail, whether it turns white, black, yellow or green
  • A change in the texture of your nail, whether it becomes more brittle or softer
  • Distortion of your nail as its shape and texture change
  • Crumbling of your nail as parts break away
  • General pain and discomfort, not necessarily to the point where you can’t walk, but if you put pressure on your nail

Fungal nail infections also have a number of common causes, although some causes are unique to certain infections.

These common causes are as follows:

  • Choosing, or not being able, to keep your feet clean and dry
  • Wearing shoes that leave your feet feeling sweaty
  • Walking around barefoot at the swimming pool or gym

On the other hand, there are some vectors which are unique to certain kinds of infection.

  • Damaging your nails allows for Candida onychomycosis to infect your toenails
  • Having a weakened immune system allows proximal subungual onychomycosis to take hold, as do having other health conditions like diabetes or heart disease. This is because of your compromised immune system.

Types of Toenail Fungus Infections

If you can pinpoint how you contracted your fungal infection, this may allow you to achieve a diagnosis. At the same time, if you have proximal subungual onychomycosis, this may also be a sign of further illness. In this instance, you should consult a doctor not just for a fungal toenail diagnosis, but a general diagnosis.

Distal Subungual Onychomycosis (DSO)

Distal subungual onychomycosis is by far the most common kind of toenail fungus. It’s also one of the most unpleasant forms of fungal toenail infection, because of its long-lasting symptoms. That being said, it can be tackled with appropriate and timely treatment, which we’ll come back to later.

What Are the Symptoms?

Distal subungual onychomycosis is caused by the very same fungus that causes athlete’s foot. That means that it commonly affects people who already have athlete’s foot, or live with someone who does. So if you already have athlete’s foot, and you have recently contracted a fungal toenail, it’s probably DSO.

A DSO infection is characterized by a number of recognizable symptoms, each of which makes it difficult to treat. DSO infects the skin underneath the nail, which is also known as the nail bed. It first infects the very top of the nail, but quickly moves along the nail towards the bottom.

The infected nail will turn either yellow or white as the condition progresses. If left untreated, the nail will begin to crumble and split, which can cause pain. Debris also gets caught underneath the nail and is particularly hard to remove, which increases the pain.

The nail will also become thicker, and the texture of your nails will change as they lose flexibility. DSO affects the nail bed and is stubborn and difficult to treat, so can be a lifelong condition. But don’t worry, because even the worst fungal nail infection is treatable with enough time and effort.

What Are the Treatments?

Because it is a stubborn condition, your podiatrist may recommend a range of treatments. This could be up to and including removing a portion of the affected nail to prevent re-infection. Infections vary among patients.

Because of its stubborn nature, treatment for DSO will most likely take longer than other forms of infection. If you receive laser surgery for toenail fungus, this will take an hour, and you will come in for repeat treatments. Your podiatrist will advise you on when they consider your treatment to have achieved its full effect.

White Superficial Onychomycosis (WSO)

White superficial onychomycosis is the next most common form of fungal infection, after DSO. White superficial onychomycosis, as per the name, is only superficial: it affects the nail, not the nail bed. This means that it is much quicker and much easier to treat, which is good news.

The first sign of WSO is that small, white spots will begin to appear on the surface of your nail. Over time, the condition will progress until the surface is covered in crumbly powder. That being said, you don’t need to let the condition affect the entire nail before seeking treatment.

Unlike DSO, the nail does not become any thicker over time, although the texture does change. And again, unlike DSO, the nail does not separate from the underlying nail bed. WSO is, therefore, less likely to become debilitating and painful, so it is considered far less serious.

White superficial onychomycosis is easily confused with a common condition which is not harmful, nor caused by fungus. WSO is commonly mistaken for keratin granulations which form as a reaction to nail polish in some people. This reaction causes a chalky, white substance to form on the nail, just like white superficial onychomycosis.

Because WSO does not infect the nail bed, you are far less likely to find walking and movement difficult. As such, whereas there is a chance that DSO may be covered by insurance, WSO certainly won’t be. But even so, you can still have it effectively treated by a podiatrist.

Because of its less serious nature, WSO is treated by ointments and creams, such as the Purely Northwest Toenail Fungus System. This is because the common side effects of oral medication are not considered worth treating the condition. Laser treatment is also a safe and non-invasive option for the treatment of WSO.

Even though it is less serious than subungual infections, it is still vital that you receive proper treatment. Any form of fungal infection progresses over time, spreads from nail to nail, and becomes more painful. It’s better to get treatment over with as soon as you possibly can, to prevent further spread.

Candida Onychomycosis

Candida onychomycosis is relatively rare and is caused by a different mechanism than WSO and DSO. CO is caused by a yeast infection, as opposed to a fungal infection, but can operate in the same way. It also has a number of similar symptoms, but there are tell-tale signs that you’re suffering from CO.

Infection with Candida begins with paronychia: literally, an inflammation and infection next to the nail. That means that the skin around the nail becomes infected before the nail itself is attacked. This method of infection is unique to candida onychomycosis, so it’s much easier to detect than other fungal infections.

From there, CO will begin to affect the nail itself, spreading from the sides of the nails to the center. Like other forms of infection, CO can affect several nails at the same time. It more commonly affects the fingernails than the toenails but is known to affect both.

CO (like DSO) can cause the nail to separate from the underlying nail bed, which is one of the most painful symptoms. Unlike other infections, however, CO changes the infected nail to a variety of different colors. The nail may become a discolored white, green, or brown, and may change shape over time.

The nail becomes thicker than normal and will show more general signs of infection like swelling and tenderness. The infection itself is more painful than the fungal forms of infection. The treatment is also different, both because of the infection’s severity and its different cause.

Just like DSO, the severity of Candida onychomycosis might mean that you need to undergo extensive treatment. This can mean taking oral medication, undergoing laser treatment and applying creams to the infected area. On the plus side, Candida onychomycosis is rare and therefore more difficult to catch in the first place.

Candida onychomycosis is caused by common yeast and is therefore contracted in the same way as athlete’s foot. It is waterborne, which is why it spreads through exercise- sweat is an excellent medium for infection! It commonly affects those who regularly have their hands in water, such as dishwater.

That’s why it doesn’t as often affect the feet, as they are submerged less often.

Proximal Subungual Onychomycosis (PSO)

Proximal subungual onychomycosis is caused by dermatophytes, the same keratin eating fungi that cause DSO and WSO. But unlike the other two fungal infections, PSO is specifically common in people who are infected with HIV.

The difference between PSO and DSO is the location of the infection, as indicated by the name. ‘Proximal’ and ‘distal’ refer to two locations of the nail and nail bed, one near and one far. The proximal nail fold is also called the eponychium and is the section of skin that partially covers the lunula.

PSO is defined by the action of the fungus, not in attacking the distal nail edge, but the proximal nail fold. This means that the infection attacks the newest nail growth, immediately after it begins to show. This is a sign that the body is immunocompromised, i.e. that their immune system is not operating properly.

PSO is identified by the white appearance of the area around the lunula, to a greater extent than usual. Whereas the lunula is normally lighter than the rest of the nail, the base becomes opaque in PSO. The infection can also spread from the base of the nail to the surrounding area of skin.

Aside from these factors, the symptoms of PSO are broadly similar to those of DSO. The nail becomes white and opaque, the texture brittle and flaky, and the nail thicker than usual. The main differentiating factor is the location of the infection at the base rather than the tip.

Because it is broadly similar to DSO, the treatment is also similar. PSO can be treated with oral medication, creams, or laser treatment- or a combination of the above. However, you may not experience a similar recovery time: PSO is harder to treat than the other forms.

That’s because PSO is usually a sign of a more important medical condition, which inhibits immune system response. As such, it is unlikely that treatment will completely cure your PSO, as the condition will recur. It is important to talk to your doctor to prioritize your care, but they’re quite likely to recommend an over-the-counter product called Xenna Nonyx Nail Gel.

Of course, PSO is not necessarily a sign of an even more important condition. That’s why you may wish to visit your podiatrist for advice on the issue. They advise you on the prognosis of treatment, how long it will take, and whether it might recur.

What If I Can’t Tell What Kind of Infection I have?

Despite having information available online, it can still be difficult to diagnose your condition. This is because while the general rules above hold true, your case may not reflect that. You may also, believe it or not, have more than one infection – although that is exceedingly rare.

There is also little to distinguish between DSO and PSO, although this isn’t of much concern. They are each treated in the same way, so that isn’t a problem. The only distinction between the two is the location of the infection.

Even if you are fairly sure of what is wrong with your nail, we still advise seeking out a podiatrist for an initial diagnosis. They will be able to identify the specific cause, fungal or otherwise, of your toenail condition. They will then be able to tell you the right treatment.

Prevention and Treatment of Toenail Fungus

Preventing Toenail Fungus From Spreading

While you can’t avoid contact with the microscopic organisms that cause toenail fungus — it’s present anywhere that is warm, dark, or moist — keeping your feet clean and dry and clipping your nails properly can help prevent an infection.

For fungus to grow, “there needs to be some type of trauma to the nail where the nail-skin junction, or natural barrier, is disrupted,” says Sheth. “For example, from a pedicure, ill-fitting shoes, or the repetitive trauma of running or hiking that causes the nail to lift or get pressed on from shoes or boots.”

Still, some people are more vulnerable than others, she adds. “Some people have it only on one toe or one foot, and some have lived with a partner who has it but they never get it,” Sheth says. “And for some you see it in their entire family. It’s not as straightforward as it seems, and it’s an annoying problem.”

If you do get a toenail fungus infection, these measures can help stop it from spreading:

  • Wash your feet and dry them thoroughly before putting on your socks and shoes.
  • Clip your toenails straight across so the nail doesn’t extend past the tip of the toe — this helps protect the delicate tissue beneath the nail.
  • Wear properly fitting shoes that allow your feet to breathe. If your feet become damp, change your socks to a dry pair as soon as possible.
  • Spray your shoes with an over-the-counter antifungal product. ”Your shoe is a great environment for fungus to thrive,” notes Sheth.
  • Wear shower shoes in public places where others typically walk barefoot, such as in locker rooms and around pools.
  • Thoroughly clean your nail clippers and other pedicure tools between use.

Getting rid of established toenail fungus can be difficult. Successfully eliminating it depends on careful adherence to a treatment plan.

“What happens over time is that the fungus breeds in the nail tissue and goes from being just a little bit on the nail, to a really discolored and thickened nail, to a nail that is totally embedded with fungus,” explains Marlene Reid, a doctor of podiatric medicine in Naperville, Illinois, and a spokesperson for the American Podiatric Medical Association.

Treating Toenail Fungus Medically

How a toenail fungal infection is treated may depend on its severity.

In white superficial onychomycosis, for example, the white patches of fungus that form on the nails can sometimes simply be filed off and an over-the-counter antifungal topical medication can be applied to the nail to kill the fungus.

For infections affecting deeper layers of the nail, over-the-counter topical medications often don’t penetrate the nail deeply enough to kill all of the fungus and prevent the infection from recurring. Repeated applications of the medication or a prescription-strength drug may be necessary.

The symptoms of more severe infections include thickened, discolored toenails that may eventually become painful. In these situations, you should see a podiatrist who can devise a treatment plan that may include these actions:

Debridement The thickened portions of the nail can be debrided, or removed, to reduce pain and allow a topical treatment to penetrate more effectively.

Topical Medication Medications that are applied like nail polish or hand cream are sometimes used to treat nail infections. However, topical medication often fails because it doesn’t move deeply enough into the nail to reach the fungus or users forget to apply it daily for almost a year, as is required.

Oral Medication Oral medications used to treat toenail fungus include terbinafine (Lamisil) and itraconazole (Sporanox, Onmel). Both medications require at least a three-month course of treatment for toenails; if used consistently, they have a good success rate. Because both drugs can affect the liver, however, blood tests of liver function are recommended before treatment is started and every four to six weeks during treatment. A third medication, fluconazole (Diflucan), is sometimes used on an off-label basis for toenail fungus caused by yeast.

Nail Removal, Home Remedies, and Laser Treatment

In the most serious instances of toenail fungus infection, the toenail may be removed surgically or dissolved with acid. This can be done to just a portion of the nail in the hope that the remaining nail will grow back healthy. In cases where the entire toenail has to be removed, artificial nails and products using light-cured resins to form a temporary covering can be used to protect the underlying tissue until the nail grows back.

If you prefer to go the home-remedy route, such as applying tea tree oil or Vicks VapoRub to your nails, keep in mind that the effectiveness of these products for treating toenail fungus hasn’t been well studied, and they are not recommended by podiatrists.

Finally, the Food and Drug Administration has approved several laser devices for “temporary increase in clear nails in patients with onychomycosis.” But while laser treatments are vigorously marketed, clinical trials of lasers have reported mixed results, and the treatments may not be covered by health insurance. If you wish to try laser treatment of toenail fungus, speak to your doctor about what to expect from the treatment, and call your insurance carrier to find out whether the treatment will be covered.

Additional reporting by Susan Jara.

man feet image by timur1970 from

Thick, rough skin under your toenails is uncomfortable and sometimes painful. Thickening toe skin may be a sign of fungus on the toes, which can be socially embarrassing and may cause toenail loss. Some toe fungi spread quickly to other toes, so it important to treat the condition when it is first detected. Even with your physician’s help, softening and thinning the skin under your toenails may take some time. With the proper care and some patience, your toe skin can return to its original soft, supple state.

Toss out your old shoes. You will need to start your foot treatment with brand new shoes. Nail fungus can live in dirty, bacteria-filled shoes. Throw away your socks, too.

Buy three or more pair of shoes and alternate wearing shoes daily. Where open-toed shoes as often as possible. Buy lightweight cotton socks

Visit your doctor and ask for a prescription like Lamisil, Novartis or Tinactin.These tablets are oral anti-fungal medications that may offer some relief.

Apply an anti-fungal topical medication to the nail, nail bed and under the toenail. If the toenail has become very thick, visit a podiatrist to have the nail filed down some. Smoothing down the thick nail will make it easier for the skin under the nail to receive the medication.

Soak your clean feet in a plastic foot tub you have filled with apple cider vinegar. Do this daily for a month. Rinse your feet with cool water after each 15-minute soak.

Pat your feet dry with a clean towel. Use an emery board or buffing pad to buff away some of the rough skin around your toes and underneath the nail. Always wash your hands afterward.

Apply Aloe Vera lotion to the skin daily to soften it.

Ever look down at your fingernails or toenails and see yellow, chalky material hiding inside? If you’re thinking, “Gross, what’s that?,” don’t freak out: it’s actually pretty common and treatable.

That chalky substance is likely keratin debris, which is formed when keratin protein (a.k.a. fibrous protein found in the nails and outer layer of the skin) breaks down, usually due to fungal infection. If left untreated, it can spread to other areas. Basically, it’s a yellowish, thick, and chalk-like substance that appears on the nails and it’s usually sharp and brittle to the touch.

While it might sound gnarly, the condition is fairly common and accounts for about half of all nail disorders, says Sonia Batra, MD, MSc, MPH, a dermatologist in Santa Monica, California, and co-host of the television show The Doctors.

“Nail keratin debris results from a fungal infection of the nail. In medical terms this is called onychomycosis or tinea unguium,” says Batra.

The fungal infection breaks down the keratin in the nail to form a white or yellow chalky substance under the nail plate.

“As keratin debris spreads under the nail, the nail plate typically becomes lifted up off of the nail bed. This separation creates a warm, moist pocket, which is even more conducive to infection,” Batra explains.The nail itself will then take on a white or yellowish color.

The nail plate itself becomes thickened from fungal infection, with crumbly, chalky keratin debris under the nail. The nails are often more fragile and jagged, she says, making it easier for them to catch on clothing or other materials.

Related: 7 Ways to Avoid Getting a Gross Toenail Fungal Infection

To prevent keratin debris from forming, you must take pains to avoid getting a fungal infection. Keep your nails clean and away from germ-filled areas, and wear flip-flops or shower sandals in moist areas, such as a public pool or shower, Batra says. When you get out of the shower, thoroughly dry your feet so moisture does not collect between the toes.

“If a fungal infection of the skin occurs (commonly known as athlete’s foot), use an antifungal cream to treat it before it spreads to nails. Also, cut nails short to prevent fungus or bacteria from finding a safe harbor under the nail,” she suggests.

If keratin debris doesn’t go away with time, you might need some extra intervention. “Some dermatologists and podiatrists treat toenail fungus and the resulting keratin debris with lasers,” Batra says. “A near infrared laser beam can be used to pass directly through the nail and vaporize the fungus, yeast or mold that is causing the infection.” The treatment usually requires two to four sessions to sufficiently kill the fungus; when completed, a healthy nail usually grows back between 9 and 12 months.

Your doctor might also prescribe topical antifungal gels or creams, lacquers and liquid solutions that can be applied topically to the nails, or oral antifungal treatment drugs, such as Terbinafine or Itraconazole, she says.

Above all else, if you’re not experiencing any toenail pain, do not try to remove the debris yourself. “Aggressive digging under the nail may worsen the ‘pocket’ for infection,” she says. So if you think you have nail debris, don’t freak out — simply head to your dermatologist to figure out the best treatment plan.

Isadora Baum Isadora Baum is a freelance writer, certified health coach, and author of 5-Minute Energy.


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What Is Paronychia?

Paronychia (pahr-uh-NIK-ee-uh) is an infection of the skin around a fingernail or toenail. The infected area can become swollen, red, and painful, and a pus-filled blister (abscess) may form.

Most of the time, paronychia is not serious and can be treated at home. In rare cases, the infection can spread to the rest of the finger or toe and lead to a deeper infection that may need a doctor’s help.

Kids usually don’t get paronychia in a toe (unless they have an ingrown toenail). But fingernail paronychia is one of the most common hand infections.

What Causes Paronychia?

Paronychia usually happens when the skin around the nail is irritated or injured. When skin gets damaged like this, germs can get in and cause an infection. These germs can be:

  • bacteria, causing bacterial paronychia
  • fungi, causing fungal paronychia

Things that can injure the skin around a nail include:

  • biting or pulling off a hangnail
  • frequent sucking on a finger
  • clipping a nail too short or trimming the cuticle
  • getting manicures
  • having hands in water a lot (as from a job washing dishes)
  • having an ingrown toenail

Kids with diabetes also have a higher chance of getting paronychia infections.

What Are the Signs & Symptoms of Paronychia?

If your child has paronychia, it’s usually easy to recognize. Look for:

  • an area of red, swollen skin around a nail that’s painful, warm, and tender to the touch
  • a pus-filled blister

Bacterial paronychia:

  • usually appears very suddenly

Fungal paronychia:

  • can take longer to notice and causes less obvious symptoms
  • can be a chronic condition (last for a long time)

Chronic paronychia can cause changes in the affected nail. It might turn a different color or look as though it is detached or abnormally shaped.

In rare cases, if the paronychia is especially severe and goes untreated, the infection can spread beyond the area of the nail.

How Is Paronychia Diagnosed?

Usually, a doctor or nurse practitioner can diagnose paronychia by looking at the infected area. In some cases, they may take a pus sample to be checked in a laboratory to see what type of bacteria or fungus caused the infection.

How Is Paronychia Treated?

Treating paronychia depends on how severe the infection is and whether it has started to spread. Often, soaking the infected nail in warm water for 20 minutes a few times a day will help it heal on its own in a few days.

If there’s an abscess, a doctor might need to drain it. In rare cases, part of the nail may have to be removed. The doctor also might prescribe antibiotics to treat the infection.

Usually, after an abscess is drained, the affected finger or toe heals quickly with no long-term problems.

For fungal paronychia, the doctor may prescribe antifungal creams, lotions, or oral (taken by mouth) medicines.

Can Paronychia Be Prevented?

Have kids follow these tips to lower their risk of paronychia:

  • Don’t bite or pick nails.
  • Trim fingernails and toenails with clippers or manicure scissors, and smooth the edges with an emery board or nail file. The best time to do this is after a bath or shower, when nails are softer. They shouldn’t cut their nails too short.
  • Don’t push cuticles back or trim them and don’t use cuticle remover. Damaging cuticles can let bacteria get into the skin and cause an infection.
  • Wear rubber gloves if there’s a chance their hands might be in contact with harsh detergents or chemicals.
  • If your child has diabetes, make sure it is well-controlled.

As much as possible, have kids try to avoid injuring their nails and the skin around them. Nails grow very slowly, so any damage to them can last a long time and increase the risk of paronychia.

When Should I Call the Doctor?

Call your doctor if:

  • Your child has paronychia that doesn’t get better with treatment.
  • The infection seems to be spreading.

Reviewed by: Elana Pearl Ben-Joseph, MD Date reviewed: August 2019

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