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Antifungal Pen - 25% Undecylenic Acid

Antifungal Pen - 25% Undecylenic Acid

The first lipophilic delivery system engineered to pass both the keratin barrier and the biofilm shield - so the active compound reaches the fungus instead of evaporating on the surface.

Regular price £14.99
Regular price £14.99 Sale price £24.99
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Targets stubborn nail fungus at its source

Supports the growth of clearer, healthier-looking nails

Helps restore stronger, healthier-looking nails fast

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My nails used to be thin and brittle, but after using this nail pen regularly, the brittleness decreased and I started seeing healthier growth. Today, my nails look noticeably stronger – a real transformation.

Olivia (before 2 months)

Description

Antifungal™ Pen is designed to support the treatment of fungal nail infections and help gradually reduce their appearance with regular use. Its formula works deep into the nail, helping to create an environment that is less favourable to fungal growth, improve nail hygiene, and support the growth of healthier, clearer-looking nails.

The lightweight texture is easy to apply and absorbs quickly, making it suitable for daily use. The product is formulated with carefully selected ingredients, has undergone quality control, and is intended for safe use according to the instructions. Suitable for anyone looking for effective nail care and support in managing fungal nail concerns.

Ingredients

Undecylenic Acid (25%)
– An antifungal active ingredient that helps inhibit fungal growth and create an environment less favourable to fungal development.

Purified Water (Aqua)
– Acts as the base of the formula and helps ensure smooth, even application.

Isopropyl Alcohol
– Helps cleanse the skin and nails while allowing the formula to dry quickly.

Denatured Alcohol
– Helps the formula spread evenly and contributes to a clean, fresh feeling.

Menthol
– Provides a cooling and refreshing sensation, helping to soothe feelings of discomfort.

Glycerin
– Helps maintain hydration and protect the skin from excessive dryness.

Borneol
– Helps soothe the skin and contributes to the overall formulation.

Net Quantity: 4 ml

How to use

  1. Clean and thoroughly dry the affected area.
  2. Twist the base of the pen to release a small amount of the formula.
  3. Use the sterile brush to apply the formula evenly to the nail plate, cuticles and under the free edge.
  4. Allow the formula to absorb fully. Wait 60 seconds before putting on socks or footwear. No rubbing is required.
  5. Apply twice daily - morning and evening - consistently for optimal results. Do not stop when the nail begins to improve.

🔁 With regular use, the product can also be used as part of a maintenance routine to help reduce the risk of recurrence.

  • For external use only. Avoid contact with the eyes.

Shipping & 90-Day Guarantee

Shipping:
Orders process in 24-48 hours. Average delivery takes 5-9 days depending on your location.

The 90-Day Biological Guarantee:
Human toenails grow slowly. We give you 90 full days to let the transungual delivery system work. If you don't see healthy, clear nail emerging from the cuticle after 90 days of consistent use, email our team for a full refund - no hassle, no questions asked.

FAQ's

Why have my past treatments failed?
Generic pharmacy liquids use water or alcohol bases that flash-evaporate on the surface. Antifungal™ uses a heavy Vitamin-E lipid carrier to channel the medicine through the hard nail plate directly to the root of the infection.

Is this safe? I'm worried about liver damage.
Yes. Unlike oral pills (Terbinafine) that process through your bloodstream and liver, Antifungal™ is a localized topical intervention. It attacks the nail fungus while keeping your metabolic and central nervous systems completely safe.

Because Antifungal™ is applied topically and does not enter the bloodstream, it does not interact with any oral medications including SSRIs, blood pressure medication, blood thinners, or diabetes management drugs.

How long until I see real results?The formula begins disrupting the biofilm immediately on first application. Within weeks 1–4, most users notice the nail softening and active spreading to adjacent toes stopping — which is the critical first confirmation the protocol is working. The first visible band of healthy, clear nail emerging from the cuticle typically appears between weeks 8–12. Full nail plate replacement — the point at which the affected nail has completely grown out — requires 6–12 months. That’s why the 90-day guarantee gives you a full three months

WARNING: This product has sold out 12 times in 2025. We recommend taking advantage of the limited availability and ordering now.
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    THE REAL PROBLEM ISN'T THE FUNGUS. IT'S GETTING THE TREATMENT THERE.

    A nail isn't simply a hard surface. Its dense keratin structure can make it difficult for topical formulas to reach the areas where fungal growth may be present.

    BARRIER 1

    The Keratin Barrier

    The nail plate is made primarily of tightly packed keratin. This creates a natural barrier between the surface of the nail and the tissue underneath.

    A formula can be applied to the outside of the nail yet still struggle to travel through the nail plate.

    If the active ingredient stays on the surface, it can't do its job where it's needed.

    BARRIER 2

    Established Fungal Growth

    As fungal growth becomes established, it can become more difficult to manage.

    Surface improvement doesn't necessarily mean the problem has completely disappeared. The nail may begin to look clearer as new, healthier-looking nail grows through, while affected nail still needs time to grow out.

    That's why consistency matters.

    THE FORMULA

    Why 25% Undecylenic Acid?

    Our Antifungal Pen contains 25% Undecylenic Acid, a recognised antifungal active used in topical products.

    But the active ingredient is only one part of the equation. The formula delivering it matters too.

    Targeted application. Consistent daily care.

    THE ROUTINE

    Consistency Matters

    Our pen is designed for convenient, targeted application directly to the nail and surrounding area, making it easy to maintain a consistent twice-daily routine.

    The goal isn't simply to make the nail look better temporarily. It's to support the gradual growth of clearer, healthier-looking nails.

    Clean. Apply. Let it absorb. Repeat.

    THE DIFFERENCE IS IN THE ROUTINE.

    Clean. Apply. Let it absorb. Repeat.

    WHY SOME FORMULAS STRUGGLE TO GET THROUGH.AND WHY OURS IS DESIGNED DIFFERENTLY.

    Same active ingredient, different outcome. The compound was never really the issue — it's whether the formula can actually reach where it's needed.

    STANDARD ANTIFUNGAL FORMULA

    NAIL SURFACE
    KERATIN PLATE
    BIOFILM LAYER
    FUNGAL COLONY
    STRUGGLES TO REACH THE FUNGUS

    Most water-based formulas sit on the nail surface. Keratin's natural structure can resist water-based ingredients, and much of the product may evaporate before it penetrates deeply enough to reach the fungal colony at the nail bed.

    ANTIFUNGAL PEN™ DELIVERY SYSTEM

    NAIL SURFACE
    KERATIN PLATE
    BIOFILM LAYER
    FUNGAL COLONY
    FORMULATED TO HELP PENETRATE
    TARGETED, CONSISTENT APPLICATION

    The Antifungal Pen's formula is designed to work with the nail's structure rather than against it, helping deliver 25% Undecylenic Acid closer to where fungal growth may be present — supporting a consistent, targeted routine over time.

    THE DIFFERENCE ISN'T THE INGREDIENT. IT'S GETTING IT WHERE IT NEEDS TO GO.

    FOUR INGREDIENTS. EACH WITH A JOB TO DO.

    No filler, no unnecessary additives — every ingredient in the Antifungal Pen is there to support the formula's performance, from the active ingredient itself to how it feels on application.

    25% Undecylenic Acid

    The Active Ingredient

    Undecylenic Acid is a recognised antifungal active. At 25% concentration, it works to help inhibit fungal growth and create an environment that's less favourable for fungal development to continue.

    Isopropyl Alcohol

    The Delivery Support

    Isopropyl Alcohol helps cleanse the nail and surrounding skin before the active ingredient is applied, and allows the formula to dry quickly — so it can be used easily as part of a twice-daily routine without disrupting your day.

    Menthol

    The Comfort Layer

    Menthol provides a light cooling, refreshing sensation on application — helping to soothe feelings of discomfort around the nail while the formula gets to work.

    Glycerin

    The Skin Protector

    Glycerin helps maintain hydration around the treated area and protects the surrounding skin from excessive dryness — an important balance, since antifungal actives and alcohols can be drying on their own.

    EVERY INGREDIENT HAS A ROLE. NOTHING IS FILLER.
    Full ingredient list: Undecylenic Acid (25%), Purified Water (Aqua), Isopropyl Alcohol, Denatured Alcohol, Menthol, Glycerin, Borneol.