Longer than anyone wants to hear — but the math is unavoidable. Toenails grow at roughly 1mm per month. Clearing a fully-infected big toenail means waiting 9–12 months for the nail to grow out, during which time you also have to keep killing the fungus so it can’t recolonize the new growth. Stage 1 cases show visible improvement in 4–8 weeks but “complete clearance” (new nail fully replacing old) takes 9–12 months minimum. Stage 3 cases with oral terbinafine plus topicals typically clear in 12–18 months. Anyone promising a 30-day cure is either selling snake oil or treating a very early surface-level case.

Yes, but less aggressively than you’d think. It’s spread through shared moisture environments — gym showers, pool decks, shared towels, shoe-sharing between family members. Household spread is most common through shared bath mats or wet shower floors. The practical fix: don’t share towels, don’t share shoes, wear flip-flops in gym showers, and wash bath mats weekly in hot water. Adults don’t typically pass it by casual contact. Children rarely get toenail fungus before puberty.

Almost always one of three sources: (1) Untreated shoes — fungal spores survived and re-seeded the new nail. Fix: SteriShoe+ UV or borate powder. (2) Untreated tinea pedis — the skin fungus on your feet re-seeded the nail. Fix: Lotrimin or clotrimazole to the foot skin daily. (3) A household member’s shoes or bath mats — spouse/roommate unknowingly has tinea pedis and you’re cross-contaminating. Fix: everyone treats, bath mats get replaced. If you’ve addressed all three and still reinfect, ask about underlying immunosuppression or diabetes — both make chronic fungal infections common.

Partially. FDA-cleared YAG laser protocols show 61–75% “clear nail growth at 12 months” — which is good but not better than oral terbinafine (76%). Laser has the advantage of no systemic side effects and no LFT monitoring, which matters for patients on multiple medications or with liver concerns. Downside: typically 3–4 sessions at $200–400 each (rarely covered by insurance) and you still need topical + shoe sanitizing adjuncts. I offer laser in Bloomfield Hills for patients who can’t take oral antifungals. For most Stage 2 patients, oral + topical is more reliable and cheaper.

Terbinafine (Lamisil) is the most common oral antifungal for nail fungus. The real-world serious liver injury rate is about 1 in 50,000 to 1 in 120,000 — low, but not zero. That’s why we do baseline LFTs and recheck at week 6. If your LFTs are normal and you’re not on interacting medications (warfarin, certain antidepressants), terbinafine is very safe. The bigger “risk” for most patients is the hassle of 12 weeks of daily pills and lab draws. For severe / stage 3 / dermatophytoma cases, it’s still the single most effective treatment available.

Partial nail removal (matrixectomy) is sometimes done for severe, painful, dermatophytoma-containing nails. But here’s the catch: if you remove the nail without killing the fungus, the new nail grows back infected. Nail avulsion alone has a 60% reinfection rate. It’s only effective as part of a combined approach: oral terbinafine + nail avulsion + topical applied to the exposed nail bed during regrowth. I only recommend full nail avulsion for painful, severely dystrophic nails where the nail is already functionally useless. For most patients, waiting out the 9–12 month clearance is better than removing the nail.

In most cases, no — it’s just a dermatophyte colonization. But new-onset fungal infections in multiple nails at once can occasionally be an early sign of immunosuppression: poorly-controlled diabetes, HIV, long-term steroid use, chemotherapy, or certain autoimmune conditions. If you’re 45+ and suddenly develop fungal infection in 3+ nails simultaneously without obvious exposure, I’d recommend basic bloodwork (A1c, CBC, HIV screen if risk factors) to rule out underlying issues. Single-nail fungus in an otherwise healthy person is almost always just exposure-related.

Trauma nails (from running, stubbing, ill-fitting shoes) are usually dark red, purple, brown, or black (subungual hematoma — blood under the nail). Fungal nails are usually yellow, yellow-white, or brown with crumbling edges. Trauma nails often resolve on their own as the nail grows out with no intervention. Fungal nails progressively worsen without treatment. If you can’t tell — or if it could be both — a podiatrist visit including a simple nail scraping + KOH test confirms fungus in 5 minutes. Call us at (810) 206-1402 for an exam.