Overview

The toenail is formed by the skin cells in the toes. It consists of a nail plate (the visible part of the nail), nail bed (the skin beneath the nail), cuticle (the tissue which overlaps the nail at the base), nail folds (skin folds that support and frame the nails from the 3 sides), lunula (the white half moon at the base of the nail) and the matrix (the part underneath the cuticle). Toenails grow from the matrix.

Toenail fungus is a fungal infection that affects the toenails, occurring between the toenails and the nail bed. Organisms that cause fungal infections require keratin to grow. Keratin is the main material that makes the nails hard. The disease is also known as onychomycosis.¹

When a dermatophyte causes toenail fungus, the condition is known as tinea unguium. It mostly affects the toenails but can also affect the fingernails.

Causes of toenail fungus

Nail infections can be caused by various fungi, yeast, bacteria and moulds. The most common type of fungus is the dermatophyte. Fungal infection of the foot can spread to the nails, and fungal infection of the nails can spread to the foot, causing athlete’s foot.(a fungal infection causing itchy, stinging, burning rash between the toes, on the top of the feet, the sole and the heels) 

People can get fungal infections from areas where fungus are present, mostly on the floor, and in public shower areas where walking without slippers is common. In addition, the usage of moist socks and shoes can also increase the risk of fungal infections. People can also be affected by fungal toenail infection by having skin-to-skin contact with someone who has a fungal infection. 

Risk factors

• Toenail fungus can affect anyone, but the risk of infection increases with age, being common in old age and rare in children under the age of 6 years
• Living in a hot and humid climate can cause sweating, which in turn makes the inside of the socks and shoes wet
• Wearing wet shoes or socks for a long time
• Walking barefoot in public areas like the gym, swimming pools, and shower rooms
• Having an injury or cut on the skin or nail
• Having wet feet or hands for more hours in a day, like spending a lot of time in water frequently
• Having a skin disease like psoriasis²
• Having other medical conditions like diabetes, and peripheral arterial disease (narrow arteries causing decreased blood flow)³
• Weakened immunity due to conditions like HIV, cancer having chemotherapy
• Not maintaining proper personal hygiene

Symptoms of toenail fungus

Tinea unguium can occur in any person. The symptoms are:

• A thickened toenail that appears deformed
• Change of toenail colour into white, yellow or brown
• Toenail separation from the nail bed, with a visible space underneath the nail
• Crack and spots on the toenail
• Unpleasant odour
• Brittle toenails
• Redness of the surrounding skin

Diagnosis

Healthcare professionals will conduct a physical examination where they will check the affected area and take the patient's disease history. A dermatologist (a skin specialist) examines the toenail fungus, and further confirmation tests may be required.

The dermatologist collects the debris from underneath the nail, it is then sent to a laboratory for further examination. In the lab, the specimen is examined under a microscope to find the cause of the infection. Proper treatment can only be given once the exact cause of infection is known.⁴

Treatment and management

Most commonly toenail fungi are treated by maintaining proper personal hygiene. In cases of severe, infection treatment is given according to the type of fungus, area of affection and severity. Dermatologists may recommend antifungal medications to treat the fungus, but it may take several months to get rid of it completely. It's important to note that toenail fungus can reoccur.

1. Oral antifungal medication

The medicines are the first choice for treatment eg Itraconazole. This antifungal medicine helps in the growth of new nails and reduces the infection. It can take several months for complete recovery.

These antifungal medicines have side effects such as rashes and liver damage, so doctors may recommend taking blood tests to check the potential medicinal side effects. Doctors may not recommend antifungal drugs to patients having liver disease or congestive heart failure.

2. Topical medication

Topical medications are available in the form of cream, gel or spray, which are applied straight on the nail. They are mostly effective when given with oral medications.⁵

3. Laser treatment

Doctors may recommend laser beams and special lights to treat the toenail fungus. However, the cure rate of laser treatment is lower than that of oral medications.⁶

4. Medicated nail polish

Healthcare providers may recommend the usage of an antifungal nail polish like ciclopirox. This is applied on the affected toenail and surrounding skin, and after seven days, it is wiped out and a new layer of medicated nail polish is applied. It may take up to a year to get rid of the fungus.

5. Medicated nail cream

Healthcare providers may suggest antifungal creams such as efinaconazole and tavaborole for treatment. The cream is applied directly and helps in reducing the effect of the fungus.

6. Surgery

Surgery is the least recommended option, where the nails are removed, and an antifungal drug is applied directly to the nail infection. 

Prevention

Anyone can be affected by toenail fungus, but by following certain measures, it can be prevented.

• Maintaining proper personal hygiene
• Usage of flip-flops in public areas like swimming pools and public showers
• Using your own shoes or flip-flops rather than sharing with anyone
• Maintaining distance from persons having a fungal infection as it may spread by skin contact
• Trauma due to accidental clipping or accidental breakage of the nail can cause the entry of the fungus 
• Clean the nail trimmer before use
• Do not rip the toenails on purpose
• Individuals with diabetes should maintain personal foot care to avoid infections
• Keep the feet dry and clean after the shower
• Soak the feet before cutting the toenails, and trim the edges carefully
• The usage of correctly fitting shoes helps protect from fungus

FAQs

Can I wear a nail polish if I have toenail fungus? 

While using antifungal cream, nail polish should not be applied. Nail polish maintains a moist environment in the nail bed, and fungus thrives on moisture. Therefore, applying nail polish can increase the fungal infection.

When should I consult a doctor?

Toenail fungus can be treated at home by maintaining proper personal hygiene. In case of high-risk patients with diabetes,  they should consult a doctor as soon as possible. When the severity of the toenail fungus increases, it is advised to consult the doctor and get proper treatment.

How to get rid of toenail fungus?

Toenail fungus can be gotten rid of by proper treatment, where administration of antifungal medications helps the process. Consistent treatment will take several months to completely get rid of the fungal infection. If the fungus is not well treated, it can grow and penetrate the skin under the nail, potentially spreading to affect the toe.

How long will it take to get rid of toenail fungus?

Treating toenail fungus can be done by using antifungal medications, but it will take several months to get rid of the fungus completely. Even if treated, there is a chance of fungal infection affecting again.

Summary

Toenail fungus is a fungal infection that affects the toenails.  It occurs between the toenails and the nail bed. A dermatophyte is a mould that mostly causes fungal infections. Dermatophytes need keratin to grow, and keratin is the main material that makes the nails hard. The disease is also known as onychomycosis. A dermatophyte-causing fungal infection is called tinea unguium. It mostly affects the toenails but can also affect the fingernails. Most commonly toenail fungi are treated by maintaining proper personal hygiene. In cases where the infection becomes severe,  treatment is given according to the type of fungus, area of affection, and severity. Dermatologists may recommend antifungal medications to treat the fungus, but it may take several months to get rid of it completely. These antifungal medicines can have side effects such as rashes and cause liver damage. Toenail fungus can return anytime.