About Kerasal
Kerasal's nail- and foot-care line traces back to Alterna LLC, founded in 2004 to bring a podiatrist-only foot ointment onto US retail shelves for the first time. That original formula, a salicylic-acid-and-urea treatment for cracked heels, became the platform the brand later extended into the Fungal Nail Renewal liquid and Nighttime Renewal Patches, both built on urea and lactic-acid keratolytic chemistry rather than an antifungal drug active. Moberg Derma acquired Alterna in 2012, and Kerasal is now marketed by Advantice Health, LLC, a US-based OTC skin, nail, and foot care company that manufactures the line domestically.
Kerasal occupies a specific, well-defined niche: a keratolytic that visibly softens, clarifies, and smooths nails damaged by fungus, rather than a drug that eradicates the underlying infection. Our own clinical reviews credit that niche directly — the Fungal Nail Renewal liquid is the most-reviewed nail-appearance product we track, with more than 66,000 verified Amazon ratings, and its brush and overnight-patch formats give buyers two distinct ways to fit a multi-month keratolytic routine into daily life.
Brand website: kerasal.com
What Kerasal makes
Kerasal's range runs wider than the products we review. The lines we know best from our own testing are marked with a star:
Kerasal Fungal Nail Renewal
brush-applied urea and lactic-acid keratolytic liquid for fungus-damaged nails — featured on BestRatedDocs
Kerasal Nighttime Renewal Fungal Nail Patches
overnight urea-glycerin occlusive patches, 14 per pack — featured on BestRatedDocs
Kerasal Multi-Purpose Nail Repair
keratolytic treatment for damaged or discolored nails beyond fungal cases
Kerasal Intensive Foot Repair
salicylic-acid-and-urea ointment for cracked heels, the brand's original 2004 retail product
Kerasal Fungal Nail Renewal Combo Pack
bundles the brush-on liquid with the overnight patches for a combined routine
Why we recognized Kerasal
The BestRatedDocs Top Brand recognition isn't paid for and can't be applied for. We award it to the brands whose products consistently stand out in our category reviews. Kerasal earned it on the strength of the products below, evaluated the same way every product on this site is: assessed against clinical criteria, verified specifications, and real-world user outcomes, and judged on merit.
Kerasal products we rated highly
Kerasal Fungal Nail Renewal Treatment
Our top pick in this category for its evidence-supported keratolytic complex of propylene glycol, urea, and lactic acid, which visibly softens and smooths fungus-damaged nail plates within about two weeks of consistent use. It carries the largest verified review base of any product in the toenail-care category we cover, with more than 66,000 Amazon reviews, and its brush applicator reaches the lifted nail edges and fissures where damage concentrates.
Read the 9 Best Toenail Fungus Treatments of 2026 guide →
Kerasal Nighttime Fungal Nail Renewal Patches
The overnight patch format delivers eight to ten hours of occlusive urea-glycerin contact while you sleep, a hands-free routine that improves compliance over brush-on liquids for a multi-month treatment window. It carries Amazon's Choice status in its category, with over 9,200 verified reviews and consistent reports of reduced nail thickness within two weeks of nightly use.
Read the 9 Best Toenail Fungus Treatments of 2026 guide → Kerasal Fungal Nail Renewal
Featured in our antifungal cream guide for the same urea and lactic-acid keratolytic complex, which softens thickened nail plates and can improve the penetration of any antifungal treatment applied alongside it. Backed by more than 66,000 verified Amazon reviews, the deepest review base of any nail-focused product in that guide.
Read the 9 Best Antifungal Creams of 2026 guide →What earned Kerasal the recognition
- Two of BestRatedDocs' clinically reviewed guides feature Kerasal products: the Fungal Nail Renewal liquid and the Nighttime Renewal Patches, both built on the same urea-based keratolytic platform.
- The Fungal Nail Renewal liquid has amassed more than 66,000 verified Amazon reviews, the largest review base of any nail-appearance product in the categories we cover.
- Originally sold only through podiatrists, Kerasal Foot Ointment moved to retail shelves in 2004, and the brand has built two decades of continuous OTC availability since.
- The liquid and overnight-patch formats solve different compliance problems — daytime brush application versus a hands-free occlusive patch — giving buyers real routine options across a multi-month treatment window.
- A patent-protected keratolytic manufacturing process underlies the product line, and the brand's current products are manufactured in the United States under Advantice Health's quality-control standards.