Nobody comes in for a thick yellow toenail on day one.
They come in three years later. After the drugstore bottle. After the tea tree oil. After the internet remedies. After a well-meaning doctor said "there's not much you can do." By then the nail is thickened, discolored, crumbling at the edge — and they've stopped wearing sandals entirely.
Here's what almost nobody explains to them: those treatments failed for specific, understandable, biological reasons. Not because the patient did something wrong. And not because nail fungus is untreatable.
Let's fix the explanation first. Then let's talk about what actually works.
Onychomycosis is a fungal infection of the nail unit. It affects roughly one in ten people overall, and the number climbs steeply with age — a substantial share of adults over 70 have it.
The organisms are usually dermatophytes — Trichophyton rubrum and Trichophyton mentagrophytes are the two big names. Sometimes it's a yeast like Candida. Sometimes it's a non-dermatophyte mold. Which organism it is matters, because they don't all respond to the same treatment.
But here is the part that changes everything about how you treat it:
The fungus does not live on your nail. It lives inside and underneath it.
It colonizes the nail bed and the underside of the nail plate. The nail plate itself — that hard keratin shield — is not the infection. It is the roof over the infection. It's dense, layered, non-porous keratin, and it was built by evolution to keep things out.
Which means it also keeps treatment out.
That one anatomical fact explains nearly every treatment failure you've experienced.
The bottle you bought at the drugstore is being applied to the top of the roof. The fungus is in the basement. Whatever antifungal is in that solution has to penetrate a dense keratin plate at a therapeutic concentration and stay there — and most over-the-counter products simply do not. They soften the surface, they change the appearance slightly, and the infection underneath continues doing exactly what it was doing.
This is not a discipline problem. Patients who apply it religiously twice a day for a year still fail. The delivery is the problem.
Prescription-strength topical antifungals — efinaconazole, tavaborole, ciclopirox — are engineered specifically to solve the penetration problem, and they are genuinely better than what's on the shelf. But even in the clinical trials, complete cure rates are modest. They work best on early, thin, limited disease — not on the thick, established, three-year-old nail that most people bring me.
They have a real role. They are rarely the whole answer.
Oral terbinafine works from the inside out. The drug reaches the nail bed through the bloodstream, which solves the delivery problem completely. It has the strongest cure rates of any single conventional therapy — and it is still not perfect. Killing the fungus is far more common than achieving a nail that actually looks normal again.
And there are real trade-offs: a 12-week course for toenails, baseline liver function testing, and awareness of drug interactions. For a healthy 40-year-old on no other medications, that's often a reasonable choice, and I recommend it when it fits.
But a large portion of the patients I see cannot or should not take it — patients on statins, patients on multiple medications, patients with any hepatic concern, patients who have already failed a full course, and patients who simply don't want a systemic drug for a toenail.
Telling those patients "there's nothing else" isn't accurate. It's just the end of the conventional playbook.
This is the one that bothers me most. Onychomycosis is not purely cosmetic. Thickened, deformed nails create pressure against the shoe, cause pain, and drive secondary problems — ingrown nails, nail bed trauma, altered gait. In a diabetic or neuropathic patient, a fungal nail is a genuine ulceration and infection risk.
It deserves treatment.
Before I treat a single nail, I want to know what I'm treating.
Here is an uncomfortable fact: a meaningful percentage of nails that look like fungus are not fungus. Nail psoriasis mimics it. Chronic repetitive trauma mimics it. Lichen planus mimics it. Onychogryphosis mimics it. In some studies, a substantial fraction of clinically diagnosed "fungal nails" come back negative on testing.
If you spend a year and several hundred dollars treating a fungal infection that isn't there, the treatment was never going to work — and the actual problem went untreated the entire time.
So we confirm. PAS histopathology, fungal culture, or PCR, depending on the presentation. It's a small step that determines whether everything after it is real medicine or an expensive guess.
Better medicine starts with a correct diagnosis. Everything else is downstream of that.
Now to the treatment people are searching for.
The device we use is the Erchonia Lunula laser, and it's important to understand that it is a fundamentally different technology from the "hot" nail lasers many practices use.
Older nail lasers work by heat. They raise the temperature in the nail bed high enough to damage fungal organisms. That can be effective — and it can also hurt. Patients describe hot, snapping sensations. There's a real risk of thermal injury to the nail bed and surrounding tissue.
Lunula is a low-level laser — photobiomodulation. It is non-thermal. It delivers light energy into the nail bed at an intensity that produces no heat at all. The patient feels nothing. No pain, no anesthesia, no downtime, no thermal risk.
Rather than cooking the fungus, it works through two parallel mechanisms:
That second mechanism is the one I care about most, and it's the same principle behind everything else we do in this practice. We aren't just attacking pathology. We are giving the tissue what it needs to heal itself.
The Lunula is the first and only non-thermal laser to receive FDA 510(k) clearance for the temporary increase of clear nail in patients with onychomycosis. That clearance was granted on the basis of a double-blind, randomized, placebo-controlled, multi-site clinical trial — Level I evidence, not marketing.
In that trial, roughly two-thirds of patients met the success threshold of 3 mm of new clear nail growth, and at six months patients averaged more than 5 mm of new clear nail.
Note carefully what that clearance says and does not say. It says temporary increase of clear nail. It does not say permanent cure. I'm going to hold that line honestly, because any practice promising you a guaranteed cure from four laser sessions is not telling you the truth.
The protocol is straightforward: four 12-minute sessions, once a week, for four weeks. All five toes are treated at once. The device runs an automated preset protocol. You sit, the laser runs, you feel nothing, you leave.
No pain. No medication. No bloodwork. No recovery.
This is where expectations get broken, so I want to be direct.
A toenail grows about 1 mm per month. A full toenail takes roughly 12 to 18 months to grow out completely.
The laser does not clear your existing nail. It cannot. That nail plate is already damaged, and damaged keratin does not heal — it grows out and gets replaced.
What the laser does is change what grows in behind it.
If a clinic tells you your nails will look better in a month, walk out.
Here is the reason I treat nail fungus differently than most.
You can kill every fungal organism in that nail bed, and the infection will still return if you send the patient back into the exact environment that created it. Killing the fungus is one variable. It is not the only variable.
Dermatophytes survive in shoes. They survive in socks. They survive on the shower floor. If we clear the nail and you put your foot back into the same shoe you've worn for four years, we have accomplished nothing durable. Shoe decontamination — UV sanitizers, antifungal sprays, rotating footwear so shoes fully dry — is not an optional add-on. It's part of the treatment.
Fungal nail infection almost never travels alone. Tinea pedis on the surrounding skin is the reservoir that continually reseeds the nail. Treat the nail and ignore the skin, and you have set a timer on the recurrence.
Repetitive trauma to the nail plate creates the microdamage that lets the fungus in and keeps it in. A hammertoe driving the nail into the toe box. A long second toe taking pressure with every step. A bunion crowding the lesser digits. Poor-fitting shoes. Runners with chronic subungual trauma.
These patients get fungal nails — and they get them again after treatment, because the mechanical insult never stopped.
If I clear your nail and never look at why that nail was being traumatized in the first place, I've treated the infection and ignored the cause. That's the pattern I spend most of my professional life arguing against — in heel pain, in tendon injury, and in nails.
Any one of those alone is a partial treatment. Together, they're an actual plan.
It's worth a serious conversation if you are:
And I'll tell you honestly who it may not be right for: someone looking for a guaranteed permanent cure, someone who won't address the footwear and skin reservoir, or someone whose nail isn't actually fungal.
If you're in one of those categories, I'll tell you that in the room.
Toenail fungus is not untreatable. It is under-treated — because most of the treatments aimed at it never physically reach it, and almost none of them address why it started.
Laser nail therapy solves the delivery problem without a systemic drug, without pain, and without downtime. It has real, peer-reviewed, placebo-controlled evidence behind it. It also has honest limits, a long timeline, and a real recurrence rate if it's used in isolation.
Used as part of a complete protocol, it works.
That's the difference between treating a nail and treating a patient.
No. The Lunula is a non-thermal, low-level laser — it produces no heat. Most patients report feeling nothing at all during the 12-minute session. This is different from older "hot" nail lasers, which work by heating the nail bed and can cause discomfort.
The standard protocol is four 12-minute sessions, once per week, for four weeks. All five toes are treated simultaneously.
Toenails grow roughly 1 mm per month. You'll typically see a band of clear new nail emerging around three months, obvious change by six months, and full grow-out of the damaged nail between 12 and 18 months. No treatment — laser or otherwise — clears the existing damaged nail.
Laser nail therapy is generally considered a non-covered service by most insurance plans and is typically a cash-pay treatment. Call our office at 305-442-1780 to discuss your specific coverage.
Yes — and it commonly does when laser is used alone. Fungus survives in shoes and on the surrounding skin, and repetitive nail trauma from toe deformities or poor-fitting footwear creates the damage that lets it back in. Durable results require treating the skin, decontaminating footwear, and correcting the mechanical cause alongside the laser.
They're different tools for different patients. Oral terbinafine has the strongest cure rates of any single therapy but requires a 12-week course, liver monitoring, and carries drug interaction risk. Laser therapy has no systemic exposure, no bloodwork, and no drug interactions — making it a strong option for patients who can't take oral medication, don't want to, or have already failed it.
If you've been told there's nothing to be done — or you've already tried everything — the next step is a proper evaluation and a confirmed diagnosis.
Katz Regenerative Foot & Ankle
Dr. Jordan A. Katz, D.P.M. — Board Certified Podiatric Foot and Ankle Surgeon
475 Biltmore Way, Suite 108, Coral Gables, FL 33134
305-442-1780 | www.anklefootcare.com
Monday–Friday, 9:00 AM – 5:00 PM
Serving Coral Gables, Miami, South Miami, Pinecrest, Coconut Grove, Brickell, Key Biscayne, and Miami Beach.
Better medicine. Better results.
This content is provided for educational purposes and does not constitute medical advice or a treatment recommendation for any individual. Individual results vary. Laser nail therapy is FDA-cleared for the temporary increase of clear nail in patients with onychomycosis. A clinical evaluation is required to determine whether any treatment is appropriate for you.
