Nail fungus: Causes, Risk Factors, Symptoms, Treatment

Nail fungus

Nail fungus, medically known as onychomycosis, is a common fungal infection that affects the toenails and sometimes the fingernails. It typically begins as a white or yellow spot under the tip of the nail and can cause the nail to thicken, discolor, and crumble at the edges over time. Nail fungus thrives in warm, moist environments such as shoes, socks, and locker rooms. It is contagious and can spread from one nail to another or to other people. Treatment options include antifungal medications, topical treatments, and in severe cases, surgical removal of the nail.

Symptoms of Nail Fungus

If you suspect you or someone else is experiencing Nail fungus, it is crucial to seek immediate medical attention by calling emergency services or consult with a Dermatologist.


  • Fungal Infections: Fungi like dermatophytes, yeasts, and molds can invade nails through cuts or separations between the nail and the nail bed.
  • Poor Foot Hygiene: Insufficient washing and drying of feet, especially after being in damp or humid environments, can contribute to fungal growth.
  • Warm and Moist Environments: Fungi thrive in warm, moist places, making places like swimming pools, showers, and locker rooms common sources of infection.
  • Wearing Tight-Fitting Shoes: Shoes that don't allow for proper ventilation can create a warm, damp environment that encourages fungal growth.
  • Nail Trauma: Injuries to nails, such as repetitive trauma (e.g., from running or sports), or even minor cuts around the nails can make them more susceptible to fungal infections.
  • Weakened Immune System: Conditions like diabetes, HIV/AIDS, or treatments like chemotherapy can weaken the immune system, making individuals more prone to fungal infections.
  • Age and Health Conditions: Aging increases the risk of nail fungus due to slower nail growth and reduced blood circulation to the extremities.
  • Nail Damage or Disease: Existing nail conditions like psoriasis or eczema can damage nails, creating entry points for fungal infections.

Risk Factors

  • Age: Older adults are more susceptible due to reduced blood circulation and slower nail growth.
  • Poor Circulation: Conditions like diabetes or peripheral vascular disease can increase risk.
  • Nail Trauma: Injuries to nails can create entry points for fungal infections.
  • Warm and Humid Environments: Such conditions promote fungal growth and infection.
  • Wearing Tight Footwear: Shoes that constrict toes can create a moist environment ideal for fungus.
  • Shared Facilities: Using communal showers, pools, or gyms increases exposure.
  • Weakened Immune System: Conditions like HIV/AIDS or treatments like chemotherapy weaken defenses.
  • Nail Conditions: Pre-existing conditions like psoriasis can make nails more vulnerable.
  • Poor Foot Hygiene: Not keeping feet clean and dry can contribute to fungal growth.
  • Genetics: Some people may be genetically predisposed to fungal infections.


Discoloration: Nails may turn yellow, brown, or white. They can also become opaque and lose their natural shine.
Thickening: Nails often thicken and become brittle, making them difficult to trim or maintain.
Distortion: The shape of the nail may change, becoming irregular or warped.
Brittleness: Infected nails tend to break easily and may crumble at the edges.
Pain or Discomfort: In some cases, nail fungus can cause mild to moderate pain, especially when pressure is applied.
Foul Odor: Nails affected by fungus may emit a foul odor, particularly noticeable when trimming or cleaning.
Separation: The nail may separate from the nail bed (onycholysis), creating a gap where debris can accumulate.
Inflammation: Surrounding skin may become red, swollen, or tender due to the infection.
Spread: If left untreated, nail fungus can spread to other nails or areas of the body.

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Clinical Examination: A healthcare provider will first examine the affected nails visually. They look for signs such as discoloration (yellowish-brown), thickening of nails, brittleness, and changes in shape.
Medical History: The doctor will inquire about symptoms, duration, and any relevant medical conditions or treatments that might predispose to fungal infections.
Laboratory Tests: To confirm the diagnosis, the healthcare provider may take nail clippings or scrapings for laboratory testing. These samples are examined under a microscope or cultured to identify the specific fungus responsible.
Wood's Lamp Examination: In some cases, a Wood's lamp (black light) may be used to detect fungal infections, as certain fungi fluoresce under ultraviolet light.
Differential Diagnosis: It's essential to rule out other conditions that mimic nail fungus, such as psoriasis, eczema, or trauma-related nail changes.
Physical Examination: Occasionally, a physical examination may include checking other areas prone to fungal infections, like the skin between toes (interdigital spaces) or the soles of the feet (tinea pedis).
Biopsy: In rare cases where diagnosis remains uncertain or treatment doesn't respond as expected, a nail biopsy may be recommended to examine tissue under a microscope.


Topical Antifungal Medications: Over-the-counter or prescription creams, ointments, or nail lacquers containing antifungal agents like terbinafine or ciclopirox are applied directly to the affected nails.
Oral Antifungal Medications: Prescription oral medications such as terbinafine and itraconazole are taken for several weeks to months, targeting the fungus from within.
Surgical Nail Removal: In severe cases or when other treatments fail, surgical removal of the nail may be necessary to treat the infection and allow for direct application of antifungal agents.
Laser Therapy: This newer treatment option involves using laser light to penetrate the nail and destroy the fungus, often requiring multiple sessions for effectiveness.
Antifungal Nail Polish: Specialized nail polishes containing antifungal agents can be used to treat mild to moderate cases of nail fungus.
Home Remedies: Some individuals try home remedies such as tea tree oil, vinegar soaks, or hydrogen peroxide soaks, although their effectiveness varies and they are not clinically proven.
Improving Foot Hygiene: Keeping feet clean and dry, wearing breathable socks and shoes, and avoiding walking barefoot in public places can help prevent and manage nail fungus.

Preventive Measures

Keep Nails Clean and Dry: Regularly wash and dry your hands and feet thoroughly, paying attention to the spaces between toes and fingers.

Trim Nails Properly: Trim nails straight across and avoid cutting too close to the skin to prevent fungal entry points.

Choose Breathable Footwear: Wear shoes made of breathable materials like leather and avoid tight-fitting shoes or socks that trap moisture.

Change Socks and Shoes Regularly: Alternate shoes daily to allow them to dry completely, and opt for moisture-wicking socks.

Use Antifungal Powders or Sprays: Apply antifungal powders or sprays to feet and shoes to reduce fungal growth.

Avoid Walking Barefoot in Public Areas: Wear sandals or flip-flops in communal showers, pools, and locker rooms.

Keep Nails and Skin Healthy: Maintain overall nail and skin health with a balanced diet and proper hydration.

Avoid Sharing Personal Items: Do not share nail clippers, socks, or shoes with others to minimize the risk of spreading fungi.

Do's & Don’t's

Do's Don't
Keep nails clean and dry Don't share nail clippers or files
Trim nails regularly Don't walk barefoot in public places
Use antifungal creams as prescribed Don't ignore symptoms or delay treatment
Wear breathable socks and shoes Don't apply nail polish on infected nails
Use vinegar or tea tree oil soaks Don't wear tight-fitting shoes that trap moisture
Practice good foot hygiene Don't use home remedies without consulting a healthcare professional
Replace old shoes or disinfect them Don't pick or tear at affected nails
Consult a doctor for severe cases Don't use unverified over-the-counter treatments

If you suspect you or someone else is experiencing Nail fungus, it is crucial to seek immediate medical attention by calling emergency services or consult with a Dermatologist.

Frequently Asked Questions
Nail fungus, also known as onychomycosis, is a fungal infection that affects the nails. It usually starts as a small white or yellow spot under the tip of the nail and can gradually spread, causing discoloration, thickening, and crumbling of the nails.
Nail fungus thrives in warm and moist environments such as public swimming pools, gyms, and showers. You can get infected by walking barefoot in these areas or by sharing personal items like towels or nail clippers with someone who has a fungal infection.
The symptoms of nail fungus may vary but often include thickened nails, yellow or brown discoloration, brittle or crumbly texture, distorted shape, and sometimes a foul odor. If left untreated, it can cause pain and discomfort.
To prevent nail fungus infections, it is essential to maintain good foot hygiene. Keep your feet clean and dry at all times. Avoid walking barefoot in public areas and wear breathable shoes made from natural materials whenever possible. Additionally, regularly trim your nails straight across to reduce the risk of infection.
There are several treatment options available for nail fungus ranging from over-the-counter antifungal creams to prescription medications and laser therapy. It is always recommended to consult a healthcare professional who can assess your specific condition and recommend the most suitable treatment option for you.
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