Thick nails can affect not only fingernails but also toenails. Affected nails may be unsightly or cause discomfort. If left untreated, thick nails can get worse and cause pain. There are many potential causes of thick nails. By understanding these causes, a person may be able to prevent thick toenails from forming and treat them quickly if they do develop.

Fungal infection is a common cause of thick nails. If the nails change unexpectedly in terms of thickness, color or texture, it is important to see a doctor to rule out any underlying condition. Treatment depends on the severity of nail changes and the underlying cause. People can often prevent thick nails by avoiding infections and irritants, and keeping nails dry. This article examines the causes, symptoms, prevention, and treatment options for thick fingernails and toenails.


Fingernails and toenails act as a strong barrier between the soft tissue of the nail bed beneath them and the environment beyond. Fingernails are useful for everyday tasks, such as scratching an itch. They also participate in the sensory functions of the fingers, providing a harsh contrast to the softer skin of the fingertip. With age, the nails can start to deteriorate or develop a disease that leads to the formation of thick nails. Although there are many potential causes of thick toenails, a fungal infection is the most likely cause for toenails.
Other pathologies, such as psoriasis or diabetes, can also be the cause of the formation of thick nails. The exact cause of thick nails will decide what treatment to follow to correct this condition.

Symptoms and Appearance

At first, thick nails may go unnoticed. However, as the nails become noticeably thicker, she may notice several symptoms, including the following:

weak, easily broken nails
a bad odor emanating from the nail
nails lift easily from the nail bed or do not appear to be fully attached to the nail bed
it is difficult to cut or trim them
the nail splits or cracks easily
dirt or other debris gets under the fingernails
pain or discomfort

As toenails thicken, they may appear rough, ridged, or scaly on the surface. Nails can also take on a yellow, green or brown hue.

Causes and risk factors

There are several reasons why nails can thicken. Most of them are related to infections or other medical issues related to thickened nails.

Some of the most common causes are listed below:

– Fungal and yeast infections

Fungal and yeast infections primarily affect toenails rather than fingernails. A type of fungal infection called onychomycosis is one of the most common causes of thick nails. Fungal infections often develop in toenails because they thrive in warm, moist environments. They spread easily and can grow rapidly, causing many of the symptoms described above. Some people are more prone to fungal infections than others. Here are some of the main causes of fungal toenail infections:

constant exposure to wet areas
binding shoes
damage to the nail or next to the nail

Also, certain health conditions can increase the risk of fungal nail infections, such as:

athlete’s foot
immune deficiencies
circulatory problems

To prevent fungal infections, avoid walking around barefoot in public places, especially locker rooms and showers. It is also important to keep shoes dry.
Doctors generally don’t consider fungal nail infections to be serious. These infections can often get better with treatment. It is not always possible for the nail to completely regain its former appearance. But treating the fungal infection can help the person reduce their discomfort and improve the appearance of the nail.

– Injury

Toenails can thicken as a result of sudden or repeated trauma or injury. It most often happens to people who play sports or exercise, such as footballers, runners, and dancers. It can also affect people who wear ill-fitting shoes. Often, thick nails due to injury are mistaken for fungal infections.
Seeing a doctor for a nail injury can help the nail grow back more normally. If the treatment is effective, improvement is likely to be slow. It takes months for the new nail growth to completely replace the length of the nail.

– Yellow nail syndrome

This less common cause of thick nails affects both fingernails and toenails. The nails become yellow, curved and thickened. A person with yellow nail syndrome usually has breathing problems and swelling in the arms and legs. This is due to an accumulation of fluid around the lungs and in the limbs. Although doctors don’t know the exact cause of yellow nail syndrome, some believe there may be a genetic link. This condition may also be associated with certain cancers and immune disorders. There is currently no treatment for yellow nail syndrome, and treatments for affected nails have limited effectiveness.

– Psoriasis

Psoriasis is an autoimmune disease that typically causes red, scaly patches on the skin. Nail psoriasis often accompanies this disease and affects both fingernails and toenails. In addition to thickening, psoriasis can also cause nail changes, such as

detachment of the nail bed
People with nail psoriasis may experience symptoms that come and go intermittently. Treatment can reduce inflammation and improve nail condition over time, but healing is usually a slow process.

– Paronychia

Paronychia is an inflammation that causes redness and swelling of the skin around the nail. Inflammation of the nail area over a long period is called chronic paronychia. It can be caused by infections or exposure to irritants, such as cleaning solutions. Over time, fingernails and toenails can become thick. A person may notice layers of the nail beginning to peel off. People can develop paronychia by frequently sucking their fingers, doing the dishes, and cutting their fingernails or cuticles too much.

Several professions also have an increased risk of developing thick nails due to paronychia. These jobs are:

the bartenders
the launderers
the cleaners

The condition usually affects several fingers or toes. Chronic paronychia can be managed by:

avoiding contact with irritants
treat inflammation
allowing the nail’s natural barrier to heal over time.

– Aging

Often, with age, toenails begin to thicken. Although this condition is most common on the toenails, it is also possible for the fingernails to thicken.
Health professionals believe that nails thicken with age due to changes in blood circulation or prolonged UV exposure. Thick nails and ridges that form on the nail due to aging are not treatable. However, a person can buff them lightly to soften their appearance.

Other causes

Rare causes of thickened nails include the following:

congenital pachyonychia, a rare genetic disease
pityriasis rubra pilaris, a rare group of inflammatory skin conditions
severe scabies infection.


Thick nails are often a symptom of another infection or disorder. In most cases, thick nails are unlikely to cause further complications. But if left untreated, they can continue to get worse, cause pain, and make wearing shoes uncomfortable. Very thick fingernails can lead to loss of hand dexterity. Seeking a medical diagnosis for thick toenails can help prevent other complications that may arise. For example, a person may need treatment for an underlying condition that affects nail health, such as diabetes.


It is possible to prevent some causes of thick nails. Thick nails are less likely to occur if the hands and feet are kept clean and dry, and if the nails are cut short. Nail infections can enter the nail through cuts or cracks in the surrounding skin. People can avoid some nail infections by keeping hands and feet hydrated to prevent cracking and by treating cuts or other skin problems.

To prevent thick nails, a person should avoid the following situations:

work in wet environments without gloves
share nail clippers
share towels
walking barefoot in public places such as gym locker rooms or showers.
People should always wear gloves when working in a damp area.

Here are more prevention tips

wear well-fitting shoes

keep socks and shoes dry


Thick nails do not always require treatment. In cases where aging causes the nails to thicken, treatment will likely be as simple as buffing rough surfaces to smooth them. In other cases, a doctor will need to prescribe treatment. The goal may be to improve the condition of the nail or to prevent it from getting worse.

Treatment options for thick nails include

prescription creams or ointments
oral medications
laser therapy or light therapy
surgery to remove the nail and allow it to grow back.
The doctor will choose the appropriate treatments depending on the cause of the thickening of the nails.


In some cases, the cause of thick nails can be benign, such as aging. In other cases, the person will need treatment to treat the underlying condition. Thick nails can sometimes be a sign of other health issues. It is important to seek medical advice and treatment when thickening or discoloration of the nails is observed. If left untreated, thick nails can get worse over time. By avoiding irritation and infection of the nail area, a person can often prevent thickening of the nails.

* criptom strives to transmit health knowledge in a language accessible to all. In NO CASE, the information given can not replace the opinion of a health professional.