Subungual warts, the kind that grow beneath a toenail, are among the most stubborn warts to treat because the nail plate acts as a physical shield that blocks topical medications from reaching the infected tissue. Trauma to the toe is typically what introduces the virus beneath the nail in the first place, and once established there, these warts resist the standard remedies that work well on exposed skin. Getting rid of one usually requires professional treatment, often involving multiple sessions and sometimes a combination of approaches, and recurrence rates after surgical removal can reach 30%.
Why Subungual Warts Are Different From Regular Warts
All warts are caused by human papillomavirus (HPV), with types 1, 2, 4, 27, and 57 being the strains most commonly responsible for the common warts that appear on hands and feet.1Journal of Wound Management and Research. Recurrent Subungual Viral Warts The virus gets into the skin through tiny breaks, and around the toes, the usual entry point is some kind of trauma: stubbing a toe, trimming a nail too aggressively, or chronic friction from tight shoes. Once the virus sets up shop underneath the nail, it grows in the nail bed, a soft tissue area that is well-protected and well-vascularized. The nail above essentially becomes a roof that the wart hides under.
This sheltered location creates a treatment dilemma. Salicylic acid, cryotherapy, and laser cauterization, the workhorses for regular warts, all struggle to penetrate the nail plate or work effectively in such a confined space. The wart can also grow into the nail matrix, which is the tissue responsible for generating new nail. Damage to the matrix during treatment can cause permanent nail deformity, so clinicians have to balance aggressiveness against the risk of lasting cosmetic and functional harm.2PubMed. Diagnosis and management of subungual and periungual verruca: A clinical review That balancing act is a recurring theme in every treatment option discussed below.
Making Sure It Is Actually a Wart
Before chasing a treatment plan, it is worth confirming the diagnosis. Subungual warts can look a lot like a fungal nail infection (onychomycosis), with thickened, discolored, or lifted nail plates being common to both conditions. A clinical review documented cases where subungual warts were misdiagnosed as fungal infections and treated unsuccessfully with antifungal medications for months before the true cause was identified.3PubMed Central. Subungual Verruca Vulgaris Mimicking Onychomycosis If antifungal treatments have not worked, a wart should be on the differential.
Dermoscopy, a technique where a clinician examines the skin through a magnifying lens with polarized light, can help distinguish the two. In subungual warts, dermoscopy reveals characteristic patterns: dotted or globular blood vessels surrounded by a whitish halo, disruption of the normal skin ridge lines, and tiny black dots representing thrombosed capillaries.4PubMed Central. Dermoscopy of Subungual Wart Those thrombosed capillaries are the classic “black seed” appearance that many people associate with plantar warts, and seeing them under the nail is a strong indicator. In ambiguous cases, a biopsy of the tissue may be needed, though clinicians try to avoid this when the nail matrix might be disturbed.
Why Over-the-Counter Remedies Usually Fall Short
The standard drugstore wart treatments, salicylic acid patches, freeze-off sprays, and similar products, are designed for warts sitting on exposed skin. Salicylic acid works by dissolving the top layers of infected tissue over weeks of daily application. When a wart is on the bottom of your foot or on a finger, you can apply the acid directly to the wart surface and it gradually eats through the infected tissue. Under a toenail, the acid cannot reach the wart without first getting past the nail plate, which is made of hard keratin and does a good job resisting chemical penetration.
Some people try filing down the nail to thin it before applying salicylic acid, and there is a logic to that approach, but it rarely reaches the deep tissue where the wart lives. Duct tape occlusion therapy, which involves covering a wart with duct tape for several days at a time, repeating the cycle for four to six weeks, has shown some promise for warts on exposed skin in children.5PubMed Central. Duct tape for warts in children: Should nature take its course? Under a toenail, however, the tape cannot make contact with the wart tissue, so its mechanism of action (thought to involve local irritation that stimulates immune response) has no real pathway to the target. For a truly subungual wart, home treatments are largely ineffective, and delaying professional care allows the wart to grow and potentially damage the nail matrix further.
In-Office Destructive Treatments
When you see a dermatologist or podiatrist about a subungual toenail wart, the conversation will usually start with one of several destructive techniques: cryotherapy, laser ablation, or surgical excision. Each has trade-offs in terms of pain, recovery time, and the risk of nail damage.
Cryotherapy with liquid nitrogen is the most widely available option. The clinician applies extreme cold to freeze and destroy the wart tissue. For subungual warts, cryotherapy is commonly used but often needs to be repeated multiple sessions because the nail plate insulates the wart from the cold.6PubMed Central. Photodynamic Therapy Combined with Liquid Nitrogen Cryotherapy and Curettage for the Treatment of Recalcitrant Periungual and Subungual Warts Some clinicians will partially or fully remove the nail before applying cryotherapy to improve access. The procedure is painful, especially around the sensitive nail bed, and blistering is expected afterward.
Carbon dioxide (COâ‚‚) laser vaporization is another option, and it is particularly useful for warts that have already failed cryotherapy. In one study, subungual warts treated with COâ‚‚ laser had a cure rate of about 65%, and when the laser was used as a first-line treatment rather than after prior failures, the cure rate climbed to 80%.7PubMed. Carbon dioxide laser treatment of periungual and subungual viral warts The laser allows more precise destruction of tissue compared to cryotherapy, which can help protect surrounding healthy nail bed. That said, it still carries a risk of scarring and nail deformity, and not all dermatology offices have a COâ‚‚ laser available.
Surgical excision, where the nail is partially or fully removed and the wart tissue is physically cut out or curetted, remains a common approach when other methods fail. Success rates for surgical removal have been reported in the range of 65% to 85%, but recurrence rates can be as high as 30%, and the procedure can leave scarring.8Journal of Wound Management and Research. Recurrent Subungual Viral Warts Recovery after nail surgery on a toe typically means several weeks of limited mobility and careful wound care, and the nail may take six months or longer to grow back fully.
Intralesional Bleomycin Injections
For warts that keep coming back or resist destructive treatments, bleomycin injections directly into the wart tissue are one of the more effective options available. Bleomycin is an anticancer drug that, when injected in tiny amounts into a wart, kills the virus-infected cells. A study treating 250 ungual warts (both around and under the nail) in 80 patients found that complete resolution required an average of about two to three sessions per patient. The treatment worked, but it was not painless: roughly four out of five patients reported moderate pain during the procedure, and about 62% of treated warts developed temporary darkening of the surrounding skin.9PubMed Central. Efficacy and Safety of Intralesional Bleomycin in the Management of Ungual Warts Serious complications like tissue necrosis were rare, occurring in just over 1% of treated warts, and those cases resolved without permanent damage.
A case report documented a teenage girl with a recalcitrant subungual wart that responded well to bleomycin injections using a “prick” method, with complete resolution and normal nail regrowth afterward.10PubMed. Complete resolution of recalcitrant periungual/subungual wart with recovery of normal nail following “prick” method of administration of bleomycin 1% The appeal of bleomycin for subungual warts is that it can be delivered directly into the wart tissue through the nail or beside it, bypassing the barrier that defeats topical treatments. The drawback is the pain, both during and after injection, which can be significant enough that patients need local anesthesia.
Immunotherapy Approaches
When warts refuse to respond to direct destruction or bleomycin, immunotherapy takes a different angle: instead of attacking the wart directly, these treatments try to wake up your immune system to recognize and fight the HPV infection itself. The most commonly used immunotherapy for subungual warts involves injecting Candida albicans antigen (a yeast extract) directly into or near the wart. The idea is that most people have been exposed to Candida before and have an immune response ready to go; injecting the antigen near the wart draws immune cells to the area, and those cells may then also attack the nearby virus-infected tissue.11PubMed Central. Fingertip ischemia following intralesional injection of Candida albicans antigen for treatment of a subungual wart
Another immunotherapy option is diphenylcyclopropenone (DPCP), a chemical applied to the skin that deliberately causes a contact allergic reaction. By provoking a localized immune response at the wart site, DPCP can help clear warts that destructive techniques cannot safely reach, which makes it particularly relevant for warts near the nail where aggressive destruction risks permanent damage.12PubMed. Factors contributing to the treatment duration of diphenylcyclopropenone immunotherapy for periungual warts DPCP treatment requires multiple office visits over weeks to months and involves intentional skin irritation, so it is not a quick fix. But for people who have been through rounds of freezing and burning without success, it offers a mechanistically different approach.
The advantage of immunotherapy is that when it works, it tends to produce more durable clearance than destructive methods alone. If your immune system learns to target HPV in that location, recurrence becomes less likely. The downside is unpredictability: not everyone mounts a sufficient immune response, and the treatments take longer to show results compared to physical destruction.
Combination Strategies and Adjunct Therapies
In practice, many dermatologists do not rely on a single method for subungual warts. A common approach is to combine a destructive technique with an immune-stimulating therapy. For example, a clinician might perform cryotherapy or curettage to debulk the wart, then follow up with intralesional Candida antigen injections or bleomycin to address any remaining virus. Some studies have explored combining photodynamic therapy (using a light-sensitizing agent and targeted light) with cryotherapy and curettage for recalcitrant periungual and subungual warts, leveraging multiple mechanisms at once.6PubMed Central. Photodynamic Therapy Combined with Liquid Nitrogen Cryotherapy and Curettage for the Treatment of Recalcitrant Periungual and Subungual Warts
On the systemic side, oral zinc sulfate has been studied as an adjunct for recalcitrant warts. A randomized placebo-controlled trial found that zinc sulfate at a weight-based dose appeared to be an effective option for warts that had resisted other treatments, with few side effects.13PubMed. Oral zinc sulphate in the treatment of recalcitrant viral warts: randomized placebo-controlled clinical trial Zinc is thought to support immune function, and while it is unlikely to clear a subungual wart on its own, some clinicians recommend it alongside other treatments. The evidence here is not overwhelming, and this was for recalcitrant warts generally rather than specifically subungual ones, but given the low risk profile of zinc supplementation, it is a reasonable add-on.
Topical formic acid, applied by puncturing the wart surface and administering the acid, showed a 92% complete clearance rate for common warts over a three-to-four-week treatment period in one study.14PubMed. Topical formic acid puncture technique for the treatment of common warts That result was for warts on exposed skin, and the puncture technique requires direct access to the wart surface, but it illustrates the kind of less-common approach a clinician might consider if standard methods have failed.
What To Expect During Recovery
Regardless of which treatment you undergo, recovery from subungual wart treatment on a toenail involves some common realities. If the nail was partially or fully removed (which many destructive approaches require for access), regrowth takes time. Toenails grow far more slowly than fingernails, typically around 1.5 millimeters per month, so full regrowth after nail removal can take anywhere from nine months to over a year. During that time, the exposed nail bed is sensitive, and you will need to keep it clean and protected.
Pain varies significantly by treatment method. Cryotherapy and laser treatments cause blistering and soreness for several days. Bleomycin injections tend to cause the most immediate pain, which is why local anesthesia is standard. Surgical excision involves the longest downtime, with limited walking expected for at least a week or two afterward. For all methods, your clinician will likely recommend keeping the toe dry, wearing open-toed shoes when possible during initial healing, and watching for signs of infection like increasing redness, warmth, or pus.
Recurrence is the most frustrating part of the process. Because HPV can persist in surrounding tissue even after the visible wart is destroyed, new warts can appear at the same site weeks or months after treatment that appeared successful. Nail unit warts are the most common nail tumor seen in clinical practice, and they carry high recurrence rates compared to warts elsewhere on the body, which adds to the distress many patients feel.2PubMed. Diagnosis and management of subungual and periungual verruca: A clinical review Being prepared for the possibility of needing a second or third round of treatment helps set realistic expectations.
Reducing the Risk of Recurrence and Spread
Warts are contagious, and the same HPV strains that caused the subungual wart can spread to other toes, your fingers (from touching the affected area), or other people through shared surfaces. During treatment and recovery, avoid picking at or scratching the wart, keep it covered when possible, and do not share nail clippers, files, or towels. In shared wet environments like gym showers and pool decks, wearing sandals or shower shoes is a basic precaution that reduces exposure.
Since trauma is a key factor in how the virus gets under the nail in the first place, protecting your toes from injury is the most practical prevention measure.1Journal of Wound Management and Research. Recurrent Subungual Viral Warts Shoes that fit well and do not chronically jam or compress the toes, careful nail trimming that avoids cutting into the nail bed, and promptly treating any toe injuries all reduce the chance of viral inoculation. People with weakened immune systems, whether from medication, disease, or other causes, are at higher risk for developing warts and for having them resist treatment, so this group may need earlier and more aggressive intervention.
When to See a Specialist and What to Ask
If you suspect you have a wart under your toenail, a dermatologist or a podiatrist with experience in nail disorders is the right provider to see. General practitioners can diagnose and initiate treatment, but the range of options for subungual warts, from bleomycin injections to immunotherapy to laser ablation, often requires a specialist’s equipment and expertise. You do not need a referral for most dermatology or podiatry visits, though your insurance plan may have its own rules.
Questions worth asking at your appointment include whether the provider has treated subungual warts specifically (as opposed to only common warts on skin), what their preferred first-line approach is, and what their plan would be if the first treatment fails. Given the high recurrence rates, asking about combination strategies upfront is reasonable. If your wart has been present for more than a year or has failed multiple treatments, asking about immunotherapy options is worth raising, since the evidence suggests these work through a different mechanism and may succeed where destruction alone has not.
One underappreciated consideration is timing. Subungual warts tend to get more difficult to treat as they grow larger and embed more deeply into the nail bed. Early treatment, ideally before the wart causes visible nail deformity, gives the best odds of a complete cure with minimal nail damage. Waiting and hoping the wart will go away on its own, which is reasonable for small warts on exposed skin where spontaneous clearance is fairly common, is a losing strategy under a toenail where the immune system has a harder time reaching the virus and the wart has a protected environment to grow in.