Kerassentials: What It Is, What It Costs and Where to Buy It

What is in each bottle

The label is published on the seller’s references page. It lists 17 ingredients, in order from the most to the least, and gives an amount only for undecylenic acid:

The full list: undecylenic acid (5%), mineral oil, sweet almond oil, organic flaxseed oil, tea tree oil, aloe vera leaf extract, canola oil, vitamin E, walnut oil, menthol, camphor oil, clove bud oil, jojoba oil, chia oil, lemongrass oil, lavender oil and manuka oil. The sales page names only 8 of them and never mentions the mineral or canola oil, and the seller’s FAQ talks of “12 carefully selected ingredients”. Each bottle holds 15 ml (half a fluid ounce).

Illustrations by Health and Wellness Studies, not to scale.

What the research shows, at a glance

Kerassentials itself has never been tested in a published study, so these ratings are for its main ingredients, from the studies in our full review:

Is it really nail fungus?

Thick, yellow, brittle or crumbly toenails are often caused by fungus, but not always. Psoriasis, repeated pressure from shoes, an old injury and other skin conditions can look exactly the same, and no antifungal, natural or prescription, will help those. A doctor or podiatrist can send a nail clipping to a laboratory to check before you commit to months of treatment.

Why toenail fungus is so hard to clear

Toenail fungus lives in and under the nail plate, a hard, layered shield that stops most of anything painted on top from reaching it. That is why prescription nail solutions are specially made to soak through the nail, why filing the surface helps, and why even the best topical treatments clear the infection completely in only a minority of people.

The infected part of the nail also has to grow out before the nail looks normal again. Toenails grow slowly, so a treatment that stops the fungus early still leaves the old, discoloured nail in place for many months. The fungus often lives on the skin as well, as athlete’s foot, which is one reason it so often comes back.

• Judge any treatment by the clear nail growing out from the base, not by the old nail.
• Treat athlete’s foot between the toes at the same time.
• Keep going for as long as the treatment directs, even after the nail starts to look better.

What works best for nail fungus

• Prescription tablets: terbinafine and azole antifungals have the best cure rates, from a 2017 Cochrane review of 48 studies with over 10,000 people. They need a doctor, because they can interact with other medicines.
• Prescription nail solutions: efinaconazole has high-quality evidence and tavaborole and ciclopirox lower-quality evidence, from a 2020 Cochrane review, though complete cure rates are modest even after about a year.
• Filing and trimming: thinning a thick nail helps any treatment reach the fungus underneath.
• Stopping it coming back: keep feet dry, change socks daily, wear sandals in shared showers and changing rooms, do not share nail clippers, and treat athlete’s foot between the toes, which can spread to the nails.

Which package makes sense?

Each 15 ml bottle is sold as a month’s supply. The packages work out to about $2.80, $2.30 and $1.63 a day, shipping included, and it is a one-time payment, not a subscription. US orders take 5 to 7 working days; shipping to Canada, the UK and Ireland, Australia and New Zealand costs $15.95 and takes 10 to 15 working days.

The awkward part is timing. A damaged toenail takes 12 to 18 months to be replaced by new growth, but the refund window closes 60 days after delivery, so you cannot judge a nail treatment before the window shuts. The “savings” on the order page are measured against crossed-out totals of $358, $537 and $1,074 that nobody actually pays.

• Two bottles ($167.99 with shipping) keep the amount you risk lowest if you just want to see whether you like using the oil.
• Six bottles ($294) give the lowest price per bottle, plus three e-books and a “surprise gift”, if you have decided to use it for many months anyway.

How to use it

• Keep the area clean and dry: wash and dry your feet well, especially between the toes, before applying it.
• Use a separate file: keep the emery board for the affected nails only, so you do not spread the fungus.
• Watch the new growth: judge progress by the clear nail growing out at the base, not by how the old nail looks.
• Stop if your skin reacts: tea tree, clove, lavender and lemongrass oils and undecylenic acid can cause redness or itching.
• Store it safely: it is for external use only, and camphor and clove oil are poisonous if swallowed, so keep it away from children.

How long it takes, and the 60-day refund

1. Write down the delivery date. The seller emails a tracking link within 60 hours of the order; the carrier’s tracking page shows the delivery date.
2. Keep the paperwork and the bottles. Save the confirmation email from ClickBank with your order number, the packing slip, and every bottle, even empty ones.
3. To claim, email the seller’s support address with “Refund Request” in the subject line, then post every bottle with the packing slip and a note giving your name, email and order number to the returns address in Aurora, Colorado, shown on the seller’s refund page. You pay the postage.
4. Allow time. The seller says refunds take 5 to 10 days to show on your statement. If you get no reply, ClickBank’s order support at clkbank.com can help.