Nail Fungus Treatment
Onychomycosis, commonly called nail fungus, is a fungal infection of the fingernails or toenails that can cause thickening, yellow or white discoloration, brittleness, crumbling edges, and separation from the nail bed. Dermatophytes are the most common cause, but yeast and non-dermatophyte molds can also be responsible, which is one reason accurate diagnosis matters. Before treatment begins, confirmation with a nail clipping, KOH prep, culture, or PCR testing can help match therapy to the organism and avoid treating look-alike nail problems such as psoriasis or trauma. At Peak Skin Center, board-certified dermatologist Dr. Thomas Knackstedt evaluates nail appearance, extent of involvement, and health factors that influence medication choice.
A key expectation in nail fungus treatment is timing: even when fungus is cleared, the nail must grow out to look normal. Toenails typically require 12–18 months to fully regrow, while fingernails regrow faster. This slow growth is why treatment courses are long and why early “success” often looks like a clean band of new nail at the base rather than an immediate cosmetic change.
Topical therapies work best for early or mild disease, superficial white onychomycosis, or when infection involves the distal nail without significant thickening. They can also be used as add-on therapy after oral treatment to reduce recurrence.
Ciclopirox 8% nail lacquer
Ciclopirox is a topical antifungal lacquer used as part of a comprehensive nail program that includes regular trimming and periodic removal of built-up lacquer. It is thought to work by inhibiting fungal growth within the nail unit and surrounding tissues. Treatment often continues for up to 48 weeks, and initial improvement may take months because visible change depends on new nail growth. Common side effects are usually local, such as mild burning, redness, or nail irritation.
Efinaconazole 10% topical solution
Efinaconazole is designed to penetrate the nail plate and reach fungus in and under the nail. It works by inhibiting fungal ergosterol synthesis, weakening the fungal cell membrane. In clinical use, it is applied daily for up to 48 weeks, and improvement typically becomes noticeable as clearer nail grows from the base over several months, with final outcomes assessed after the treatment course. Common side effects include application-site dermatitis, vesicles, pain, and a small risk of ingrown toenail.
Tavaborole 5% topical solution
Tavaborole is an oxaborole antifungal that interferes with fungal protein synthesis by targeting a fungal enzyme involved in translation, which disrupts fungal growth. It is applied once daily for 48 weeks, and visible improvement usually takes months as the nail grows out. Common side effects are mostly local and include application-site exfoliation, redness, dermatitis, and ingrown toenail.
Oral therapy is often considered when multiple nails are involved, nail thickening is significant, infection reaches the nail matrix, or topical therapy is unlikely to penetrate adequately. Evidence reviews frequently identify oral terbinafine as a highly effective first-line option for many dermatophyte infections when there are no contraindications. At Peak Skin Center, Dr. Thomas Knackstedt weighs effectiveness, safety monitoring needs, drug interactions, and organism type.
Terbinafine
Terbinafine concentrates in keratin and targets dermatophytes by inhibiting squalene epoxidase, disrupting fungal cell membrane production. A commonly used regimen is 250 mg daily for 12 weeks for toenails (and 6 weeks for fingernails). Early improvement may be noticed after several months when healthy nail growth becomes visible, but full cosmetic improvement can take up to a year or longer for toenails because of slow regrowth. Common side effects include gastrointestinal upset, headache, rash, and taste disturbance; liver-related adverse effects are a key consideration, so clinical oversight and appropriate lab monitoring may be used depending on history and risk factors.
Itraconazole
Itraconazole works by inhibiting ergosterol synthesis, weakening the fungal cell membrane, and it has broader activity that may be useful when non-dermatophytes or yeast are suspected. Dosing may be continuous or “pulse” based depending on the nail involved and clinical context. As with other therapies, visible improvement often takes months and correlates with new nail growth. Common side effects can include nausea, abdominal discomfort, headache, and important drug–drug interactions; liver effects and heart-related warnings are considerations in appropriate candidates, which is why dermatology-guided selection is important.
Fluconazole (selected cases)
Fluconazole is sometimes used off-label in certain scenarios, particularly when yeast is involved or when other agents are not suitable. It works by inhibiting fungal ergosterol synthesis. Time to visible improvement still depends on nail growth, often requiring several months. Potential side effects include gastrointestinal upset and liver enzyme elevation, and drug interactions can be clinically relevant.
Onychomycosis treatment is most successful when the diagnosis is confirmed, the organism type is considered, and expectations match the slow pace of nail regrowth. Peak Skin Center creates individualized nail fungus treatment plans for patients in Cary, Apex, Holly Springs, Fuquay-Varina and beyond. Our clinical team may combine topical therapy, oral antifungals, and in-office nail debridement to improve medication penetration and long-term clearance.
At a Glance
Dr. Thomas Knackstedt
- Double board certified in dermatology and Mohs Surgery
- Over ten years of experience providing evidence-based care
- Nationally renowned physician leader with numerous publications, lectures, and academic affiliations
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