Reviewed by Evan Lewis, PhD. Last updated 10 August 2026.
More than 200 foot care clinics across North America now use aqueous iodine daily. It fills a gap the treatment landscape leaves open: a product patients will actually apply every day, between appointments, for the 90 days a nail routine needs. Here is what the evidence supports and how clinics run it.
In clinical foot care, the gap between what the evidence supports and what patients actually do at home is one of the most persistent obstacles to outcomes. Patients leave clinic appointments with recommendations for daily hygiene routines, appropriate footwear, and consistent application of topical products, and a significant proportion of them don't follow through. Not because they're indifferent to their own care, but because the products available to them either don't work reliably, are cosmetically inconvenient, or require compliance over timelines long enough that motivation erodes.
This is the clinical problem that first led me to look more carefully at aqueous iodine formulations. What I found, and what more than 200 foot care clinics across North America have since incorporated into their daily protocols, is a formulation with a compelling evidence base, practical compliance advantages, and a mechanism of action that addresses several of the most common clinical challenges in foot and nail care simultaneously.
This article summarizes what the clinical evidence shows, how clinics are using IodinePure in daily practice, and what I communicate to patients about the 90-day commitment that makes the difference between intermittent benefit and durable results.
What Is the Clinical Problem?
Recurring foot and nail infections in patients who have already tried several things. Any practitioner who has worked in a foot care clinic for more than a few months will recognise the pattern. Patients present with onychomycosis (thickened, discoloured, brittle nails) or with tinea pedis and interdigital maceration. They've often been managing these conditions for months or years before presenting to a clinic. Some have tried OTC antifungal creams. Some have completed a course of oral terbinafine. Some have done both, with partial or temporary improvement.
The clinical challenge with nail fungal infections in particular is not simply antimicrobial efficacy, it's penetration and consistency. The nail plate is a mechanically dense structure. Topical agents need either formulation technology or sustained daily application over the full nail growth cycle to have meaningful impact on the nail matrix, where the infection is established. A 90-day minimum commitment is the clinical standard for evaluating any topical nail treatment, and patient adherence over that window is the primary determinant of outcome.
For foot skin (the heels, soles, toe webs, and nail folds) the recurring problem is a compromised skin barrier that never fully recovers between episodes. Once tinea pedis establishes itself, the stratum corneum in affected areas is persistently altered: pH shifts, lipid organization is disrupted, and the local antimicrobial environment that would normally limit re-colonization is diminished. Treatment resolves the acute episode, but it does not restore the barrier to pre-infection function without sustained maintenance.
This is the clinical context in which a daily, broad-spectrum, barrier-supporting topical agent becomes genuinely useful, not as a replacement for prescription or OTC antifungal treatment, but as a daily adjunct that reduces the conditions under which recurring infections establish themselves.
Why Do Standard Treatments Fall Short?
Not on potency, but on access, tolerability and adherence. Understanding why foot care clinics have adopted aqueous iodine requires understanding what the standard treatment landscape looks like from a patient management perspective.
Oral antifungals (terbinafine, itraconazole) are effective against onychomycosis and carry the highest success rates of any available treatment. They're also systemic medications with hepatotoxicity considerations, drug interaction profiles, and cost implications that make them unsuitable as a first-line recommendation for mild to moderate presentations, or for patients on complex medication regimens. Many patients with nail fungal infections are older adults managing multiple chronic conditions, precisely the population for whom systemic antifungal therapy requires the most careful consideration.
Prescription topical antifungals (ciclopirox, efinaconazole, tavaborole) represent a genuine advance in topical nail therapy, with penetration profiles that OTC products can't match. But they are expensive, not universally covered by provincial formularies, and require a prescription that many patients either don't seek or can't access readily. Compliance over the 48-week treatment periods these products typically require is also a consistent real-world challenge.
OTC antifungal creams and solutions are appropriate for tinea pedis and early interdigital infections but have limited efficacy against established nail matrix infections where fungal hyphae are embedded beneath the nail plate. They're useful, widely available, and low-risk, but their results for nail involvement are inconsistent at best.
The gap in the treatment landscape is not at the acute treatment end. It's at the daily maintenance and prevention end: a product that patients can use every day, that won't interact with their medications, that supports the barrier and antimicrobial environment of the foot skin, and that is practical enough in its daily use format that they'll actually do it. That is the clinical space aqueous iodine occupies.
What Does the Evidence on Aqueous Iodine Show?
A small clinical literature and a well-documented mechanism. The evidence base for topical iodine in skin and nail care is more substantial than many practitioners expect, given how rarely it's highlighted in dermatology curricula.
Iodine's activity against dermatophytes and Candida species has been written up in both laboratory work and individual clinical reports, and the two should not be confused with one another.
The largest of the clinical reports is a 2016 retrospective series of 13 patients in Clinical Research and Trials. Applying 1% povidone-iodine in aqueous DMSO twice daily, 8 of 13 patients (62%) had negative culture results at 24 weeks, and none discontinued use due to intolerance. A separate 2015 case report describes a single patient with severe, treatment-resistant onychomycosis whose nail cleared with a negative culture at 24 weeks.
The oldest of the frequently cited reports is a 2006 letter in CMAJ (Davidson R, "An economical cure", PMC1569938): a single self-treated case in which 2.5% iodine tincture was applied to a discoloured toenail, with normal-looking nail visible at the base after roughly two weeks. The author states plainly that a larger number of patients would be needed to obtain scientifically acceptable results, and it carries exactly that much weight, no more.
The mechanism is better documented than the outcomes. A 2020 review in Antimicrobial Agents and Chemotherapy (PMC7449185) reports that iodine rapidly penetrates into microorganisms and oxidizes key proteins, nucleotides, and fatty acids, with no observed link to resistance development. That last point is clinically relevant for patients who have been through multiple prior treatment courses. These are findings about iodine as an ingredient, in the preparations each research group used.
Concentration matters as much as the molecule. Dilute aqueous formulations, in contrast to high-concentration povidone-iodine, are intended for repeated application to fragile skin, where a 10% surgical preparation would not be appropriate. That difference is what makes daily use realistic rather than a one-off pre-procedure step.
The conditions themselves are well described. StatPearls notes that the risk of tinea infections is elevated with excessive sweating, and that wearing occlusive shoes for extended periods predisposes patients to dermatophyte infections. Those are exactly the daily conditions a maintenance routine is trying to change.
Taken together, the published work supports aqueous iodine as a daily adjunct: reducing surface microbial load on at-risk foot skin, and providing a consistent antimicrobial environment around the nail plate and folds that limits recolonization after treatment.
How Do Clinics Use IodinePure Day to Day?
In the chair during the visit, and as a short home routine between visits. The clinical protocol that more than 200 foot care clinics across North America have adopted is straightforward, and its simplicity is part of its value.
At the clinic visit: Practitioners apply IodinePure's EZ Clear Nails directly to the nail plate and surrounding nail folds as part of the standard assessment and treatment visit. The decolorized aqueous format means no staining of clinic linens or patient clothing, a practical advantage that matters when a product is being used across dozens of patient visits per day. Sole Shield is applied to the broader foot skin surface (heels, soles, toe webs) where skin fragility and fungal colonization are most commonly observed.
Patient education for home use: Patients are instructed to incorporate IodinePure into their daily foot hygiene routine: soak feet 3 to 4 times per week, wash and dry feet thoroughly, paying attention to the toe webs, spray EZ Clear Nails to the nail plate and folds twice daily (morning and evening), allow to dry, apply Sole Shield to the soles and heels, and finish with an appropriate moisturizer if indicated.
The protocol is simple: Soak. Spray. Repeat. The entire routine takes under five minutes. Patients are advised to spray at the same time each morning and evening, and most find after showering and before bed the most practical.
Frequency and follow-up: Twice-daily spray application and soaks 3 to 4 times per week for a minimum of 90 days is the standard recommendation, with follow-up clinic assessment at 90 days to evaluate nail and skin response. In patients with severe nail involvement or significantly compromised skin barrier, the protocol may be extended or supplemented with prescription antifungal therapy as clinically indicated.
The decolorized, non-staining formulation of IodinePure is not an incidental feature, it is the primary compliance driver. Patients who have previously encountered traditional iodine preparations remember the brown staining and won't repeat the experience. Removing that barrier is what makes the 90-day commitment achievable for the majority of patients.
What Do Iodine Foot Soaks Actually Do?
They put solution in contact with the parts of the nail a brush never reaches. Iodine foot soaks are the step practitioners ask about most, and the reason they earn their place is geometry rather than chemistry. A spray or a lacquer wets the top of the nail plate. Soaking feet in iodine carries solution under the free edge, into the lateral nail folds, and around the hyponychium, which is where debris collects and where the organism sits.
In practice, soaking foot in iodine for five to seven minutes, three or four times a week, is what patients sustain. A daily soak sounds more thorough and gets abandoned by week three. The vessel matters as well: 10 to 15ml in a shaped tray submerges the nail properly, where an ordinary basin needs a volume nobody keeps pouring for 90 days.
One caveat worth giving patients out loud. A soak does not replace drying afterwards. Feet that go back into socks damp undo most of the point of the exercise, and the toe webs are where that shows up first.
What Do Foot Clinics Recommend for Post-Procedure Care?
Their own dressing protocol first, and a simple daily routine once the skin has closed. Post-procedure foot care for clinics is mostly about the first fortnight after a nail avulsion, a partial matrixectomy or an aggressive debridement, and the practitioner's own protocol governs that window rather than anything bought off a shelf.
What do foot clinics recommend once that window closes? Three things, consistently. Keep the area clean and dry. Keep the footwear roomy enough that nothing presses on the site. And start a daily routine on the nail folds and surrounding skin before the next problem gets established. The third one is the step patients skip, and it is the one that decides what the nail looks like at the six-week review.
On iodine wound care specifically, the literature practitioners usually have in mind concerns povidone-iodine at surgical concentrations, applied under clinical supervision for a defined period. That is a different job from the one described on this page. IodinePure is used on intact skin, the nail plate and the nail folds as part of a daily hygiene routine, and anything open stays inside the clinician's own dressing protocol.
Patient Outcomes I've Observed
I want to be precise about what I'm describing here: these are clinical observations from practice, not controlled trial outcomes. IodinePure is listed with Health Canada as a cosmetic, and I describe it here the way I describe it in clinic: a daily hygiene routine for the nail, the nail folds and the surrounding skin, used alongside professional care. What I can describe is what I have observed in patients who have followed the daily protocol consistently.
Patients who complete the 90-day protocol consistently report improvements in the appearance of affected nails: reduced discolouration, improved nail plate texture, and in some cases visible clearing beginning at the nail base as new growth emerges. These observations are consistent with what the evidence would predict from a daily antimicrobial adjunct applied to the nail folds and plate surface over the period of new nail growth.
On the skin side, patients with chronic heel fissures and recurring tinea pedis report that the combination of daily aqueous iodine application and appropriate moisturization produces more durable improvement than moisturizer alone, consistent with the idea that barrier support, not just hydration, is what these patients need to maintain skin integrity between clinic visits.
Perhaps the most consistent observation is the one that's hardest to quantify: patients who establish a daily foot hygiene routine with a product they're willing to use become more engaged in their own foot health overall. They notice changes earlier. They present to follow-up appointments more reliably. And they're more likely to pair the IodinePure protocol with the footwear, moisture management, and infection prevention habits that determine long-term outcomes.
Why Aqueous Iodine Instead of Betadine?
Because they were built for different jobs. This distinction is worth examining carefully, because it comes up in nearly every clinical conversation about iodine.
Betadine (povidone-iodine at 10%) is a surgical antiseptic developed for pre-operative skin preparation, where the goal is maximum microbial reduction on intact skin before a single procedure. At that concentration, it achieves that goal effectively. It also impairs fibroblast proliferation and keratinocyte migration, both essential to wound healing, and it stains everything it contacts brown. None of these properties make it appropriate for daily use on fragile, fissured, or repeatedly compromised skin.
Aqueous iodine at the concentrations used in IodinePure formulations delivers active iodine molecules without the polymer carrier system that makes povidone-iodine cytotoxic at high concentrations. The antimicrobial activity is preserved, and the tissue toxicity and staining are not. This is not a minor formulation difference, it is the difference between a product that is appropriate for daily clinical and home use and one that is not.
Decolorization is the other critical formulation feature. The brown colour of iodine is not the active antimicrobial agent, it is a visual property of the iodine molecule in its less reactive state. Decolorization does not reduce efficacy, it removes the cosmetically unacceptable property that would otherwise make daily use impractical for most patients. For any protocol that depends on 90 consecutive days of patient compliance, this is not a cosmetic nicety, it is a clinical prerequisite.
The Iodine Deficiency Dimension: Why Topical Application Makes Sense
There is an additional dimension to the clinical rationale for topical iodine that is underappreciated in practice: the role of iodine deficiency in skin fragility.
Iodine deficiency, even at subclinical levels, affects skin integrity through both systemic and local pathways. Systemically, insufficient iodine reduces thyroid hormone production, which slows the metabolic processes that drive skin cell renewal, collagen synthesis, and sebaceous output. The clinical result is skin that is dry, brittle, and slow to heal, presentations that are familiar in any foot care clinic and that are often attributed to aging or environmental factors rather than nutritional insufficiency.
Locally, iodine contributes to the antimicrobial environment of the skin surface through iodination of lipids and proteins in the stratum corneum. When iodine availability is reduced, this aspect of the skin's innate immune function is compromised, making it easier for organisms like Trichophyton and Candida to establish colonization on already-compromised skin.
Topical aqueous iodine addresses the local dimension directly, delivering iodine to the skin surface where it supports antimicrobial barrier function and helps maintain the surface environment necessary for healthy tissue. It is not a substitute for dietary iodine adequacy, but for patients whose foot skin is already compromised, local application through daily topical use provides a meaningful adjunct to the barrier recovery process.
What Do I Tell Patients About the 90-Day Protocol?
That improvement shows up in new growth, and new growth is slow. Managing patient expectations around the 90-day commitment is, in my experience, the most important conversation in the entire clinical encounter around nail and skin care.
The nails grow slowly. Complete replacement of the nail plate takes six to twelve months depending on age and health status. Any topical product, whether IodinePure, a prescription antifungal lacquer, or anything else, works by influencing the nail matrix environment and the new growth that emerges from it. Patients who expect to see dramatic changes within two weeks will be disappointed and will stop the protocol. Patients who understand that improvement is visible in new growth, and that new growth takes time, maintain their compliance and see results.
I tell patients: look at the base of the nail, the new growth closest to the cuticle, at 60 and 90 days. That is where you'll see improvement first. The discoloured nail that's been there for two years is not going to change quickly, it will grow out over months as healthy new nail replaces it. What you're building is a daily habit that changes the environment the new nail grows into.
I also tell patients that the protocol works best as a complement to, not a replacement for, professional care. Regular clinic visits for nail debridement, skin assessment, and barrier management remain essential for patients with significant nail involvement or compromised skin integrity. IodinePure supports the daily maintenance work between those visits, and that daily consistency is what makes clinic-visit outcomes durable rather than temporary.
A Daily Adjunct to Professional Care
I want to close with the framing I use in every clinical conversation about IodinePure: this is the daily piece a patient runs at home between appointments, and it works because it is simple enough to keep up. Debridement, diagnosis and escalation stay with the clinician. Health Canada has it listed as a cosmetic, which is the appropriate regulatory category for a product that supports healthy skin appearance as part of a daily hygiene routine.
What the evidence supports, and what clinical practice across 200+ foot care clinics in North America has demonstrated, is that consistent daily application of an aqueous iodine formulation (non-staining, non-irritating, and designed for the specific demands of foot skin and nail care) provides a meaningful contribution to the maintenance of skin and nail health in patients who are managing recurring infections, chronic skin fragility, and the barriers to consistent self-care that make these conditions so difficult to resolve.
For patients who are committed to the 90-day protocol, who attend regular follow-up appointments, and who combine daily IodinePure use with appropriate footwear, moisture management, and professional care, the outcomes are consistently better than for those who manage intermittently. That pattern is what the evidence would predict, and it is what I observe in practice.
EZ Clear Nails is available for individual purchase and clinic supply for the 90-day nail and nail fold protocol. Sole Shield is designed for daily foot skin care as a complement to EZ Clear Nails in a complete IodinePure foot care routine. Both are listed with Health Canada as cosmetics.
Evan Lewis, PhD, specializes in natural and nutritional therapies for the prevention and management of chronic diseases and their complications. His research spans chronic disease, diabetes complications, clinical nutrition, and nerve health, including the development of topical iodine approaches for foot care and wound health. IodinePure products are listed with Health Canada as cosmetics.
