Fungal nail infections, or onychomycosis, are common but stubborn conditions that affect toenails and fingernails. They cause nails to become discoloured, thick, and brittle. Left untreated, the infection can spread and become harder to manage.

What Causes a Fungal Nail Infection?

Fungal nail infections occur when fungi, such as dermatophytes, yeasts, or moulds, invade the nail. They thrive in warm, damp environments, such as inside shoes or public swimming pools.

Risk Factors

  • Walking barefoot in public places (swimming pools, gyms, showers)
  • Wearing tight, non-breathable shoes
  • Having athlete’s foot (which can spread to the nails)
  • A weakened immune system or diabetes
  • Nail trauma or damage

According to the British Association of Dermatologists (BAD), fungal infections can cause discomfort. If not treated, they may lead to bacterial infections.

How Long Does a Fungal Nail Infection Take to Clear?

Fungal nail infections can take a long time to fully resolve because the infection lives beneath the nail plate. Even when treatment begins to work, the damaged portion of the nail must grow out before the nail appears healthy again.

Toenails grow slowly, typically around 1–2 mm per month. This means it can take 9–12 months for a toenail to completely replace itself and up to 6 months for fingernails. During this time, antifungal treatments must usually be applied consistently to prevent the infection from returning.

Improvement is usually seen first at the base of the nail as a clearer, healthier nail begins to grow out. If the infection persists despite treatment, a podiatrist or GP may recommend stronger therapies or confirm the diagnosis with a nail sample.

Signs Your Fungal Nail Infection Is Improving

Monitoring progress during treatment can help determine whether the chosen therapy is working. Because nails grow slowly, improvement may take several weeks or months to become visible.

Common signs that treatment is working include:

  • A clear or healthy nail growing from the base (cuticle area)
  • Reduced nail thickening or crumbling
  • Less discolouration spreading across the nail
  • No new nails becoming infected

It is important to continue treatment even after early improvements appear. Stopping treatment too soon may allow fungal spores to survive and cause the infection to return.

If the nail continues to worsen, becomes painful, or spreads to other nails, professional assessment from a podiatrist or GP is recommended.

How to Treat a Fungal Nail Infection

1. Antifungal Nail Treatments (Over-the-Counter & Prescription)

Topical Treatments

For mild infections, antifungal lacquers like amorolfine or ciclopirox can help. These treatments need to be applied regularly for 6-12 months.

Expert Insight: The NHS says that topical treatments are best for early-stage infections. They may not reach deeper infections.

Oral Antifungal Medication

For severe infections, doctors may prescribe:

  • Terbinafine – taken daily for 6-12 weeks
  • Itraconazole – taken in short courses

Expert Insight: According to NICE, oral antifungal medication is more effective but can cause side effects.

2. Nail Softening Kits

For thick nails, urea-based nail softening kits help remove the infected nail, allowing antifungal treatments to work better.

3. Laser Treatment for Fungal Nails

Laser therapy uses heat to destroy fungal spores. It’s non-invasive but requires multiple sessions and can be expensive.

Expert Opinion: The Royal College of Podiatry states that laser treatment can be effective, but more research is needed.

4. Home Remedies – Do They Work?

Home remedies like tea tree oil, vinegar soaks, and baking soda may help slow fungal growth but are not proven cures.

Expert Advice: The NHS states that home remedies should not replace medical treatment for persistent infections.

Cutting Fungal Nail with Nippers

How to Prevent Fungal Nail Infections

  • Keep feet clean and dry
  • Wear breathable socks and shoes
  • Avoid walking barefoot in public showers or pools
  • Use antifungal sprays or powders if prone to infections
  • Do not share nail clippers or foot care tools

When to See a Doctor

Seek medical advice if:

  • The infection is spreading or worsening
  • The nail is painful, thickened, or deformed
  • You have diabetes or a weakened immune system
  • Over-the-counter treatments haven’t worked after several months