Nailing Treatment of 3 Nail Disorders: Nail Lichen Planus, Psoriasis, and Onychomycosis

When it comes to nail disorders, early diagnosis and aggressive treatment can mean the difference between preserving the nail and permanent damage. Nail lichen planus, psoriasis, and onychomycosis each present unique challenges that demand tailored therapeutic approaches.

Boni E Elewski, MD, professor and chair of dermatology at the University of Alabama at Birmingham, and the James E. Elder, MD, Endowed Professorship for Graduate Education, covered how to recognize and use evidenced-based treatments for the disorders in her presentation Nailing the Difficult to Treat Nail Disorders, at the 2025 Midwinter Clinical Hawaii Dermatology Conference, held February 15-29, 2025, on the Big Island, Waikoloa Village, HI.

Elewski began with images of nail lichen planus (NLP), illustrating the characteristic signs of the disorder. In the early stages, you see longitudinal fissures and a brittle thin nail plate, or onychorrhexis. "The nail gets thin. You see ridges. You may see redness—we call it erythronychia. The nail's brittle and it infects, generally, all nails," she explained. “If you don't treat, you can end up with anonychia—no nail. This is a nail emergency."

Treating Nail Lichen Planus: Go Systemic

In the early stage, NLP is treatable. The best option? Agreement is wide: topical treatments are ineffective for nail lichen planus. "If you thought of a topical treatment, you're wrong. Topicals don't work," Elewski emphasized. There are no current published guidelines for management of NLP, but Elewski said that systemic therapy is considered more frequently and that JAK inhibitors have emerged as a more targeted and effective therapy,1 particularly for patients with concurrent eczema. "Actually, I think JAK inhibitors are probably our best option going forward, if you can get [them] approved."

Among the effective JAK inhibitors Elewski pointed to baracitinib,2 upadacitinib, abrocitinib, and tofacitinib.3 "They calm down the lichen planus and then patients are probably fine going forward," she said, noting that patients won’t need to continue on the drug for years and estimating a treatment duration of 6 to 12 months.

Prior to the advent of JAK inhibitors, the go-to may have been topical clobetasol, or intralesional corticosteroid into the nail matrix, which Elewski said she would accept if a patient presented with a single abnormal nail. “But 10 nail injections? No, not easy, not good.”

Nail Psoriasis: Systemic vs. Topical

Like nail lichen planus, nail psoriasis can be the sole manifestation of disease, which makes a thorough patient history and examination essential: "I see a lot of children who come into my office with bad fingernails but no skin psoriasis. When you dig deeper, you find they play the piano or guitar—activities that can traumatize the nail." She stressed that other areas still should be considered and examined, such as the scalp, the genital area, inverse areas, and ask about psoriatic arthritis. Just 5% of patients with psoriasis have only nail disease, Elewski added and about comorbid psoriasis and psoriatic arthritis. “It kind of goes together," she said, estimating a co-occurrence rate between 50% and 80%.

Classic signs of nail psoriasis include pitting, the most common, onycholysis with a red border, and oil spots on the nails. Splinters and nail bed hyperkeratosis are also common.

Considering the best treatment for nail psoriasis Elewski acknowledged that there are oral drugs that work very well but she moved on to highlight a Bayesian network analysis of 4 head-to-head trials evaluating biologics for complete resolution of nail psoriasis.4 The conclusion was that the IL-17 blocker ixekizumabwas most effective treatment.4 "Not surprising,” Elewski added, “because drugs that work in the joint are going to work in the nail."

She referred to a consortium of dermatologists and nail experts, led by Dimitrios Rigopoulos of the University of Athens, that published a 2-part recommendation for the definition, evaluation, and treatment of nail psoriasis in adults with mild or no skin psoriasis.5 For patients with 4 or more affected nails, systemic therapy is recommended. Options include apremilast, deucravacitinib, or IL-17 inhibitors.

For cases involving 3 or fewer nails, topical therapies may suffice.5 "You could inject each nail with triamcinolone, but that's painful," the speaker acknowledged. Instead, a rotational treatment combining vitamin D solution (weekdays) and clobetasol solution (weekends) can be effective. Elewski described a study with 62 participants with 142 abnormal fingernails. Using the rotational regimen returned a 72% reduction in hyperkeratosis at 6 months and 81% at 12 months with no significant adverse events.6 She cautioned, however, that prolonged steroid use around the nail carries risks: "Topical steroids around the bone can cause atrophy, leading to a shortened finger—the disappearing digit."

Onychomycosis: Facing Drug Resistance

Onychomycosis primarily affects toenails and requires confirmatory testing. "Even I might look at a nail and not be 100% sure there's fungus there," the speaker admitted. Diagnostic options include KOH preparation, PAS stain, fungal culture, or PCR analysis.

Treatment regimens have evolved in response to increasing resistance, which Elewski demonstrated in her presentation is global. "In 2017, about 1% of Trichophyton rubrum isolates were resistant to terbinafine. By last year, that figure jumped to 19%" Elewski warned. This alarming trend is requiring longer and more aggressive treatment. "I would give terbinafine for a minimum of 6 months. The new recommendation is to double the dose from 250 to 500 mg daily."

Itraconazole is another option with dosing recommended at 200 mg daily for 6 to 8 months (note: pay attention to labeling updates). Elewski is a fluconazole fan and approaches her patients with the "Fungal Friday" regimen:200 to 400 mg once or twice weekly until nails are normal.

When standard therapies fail, adjunctive agents like efinaconazole or amorolfine may help. "We have to be more aggressive, treat longer, and hope we can get rid of the patient's fungus."

Elewski wrapped up her presentation with a short segment on nail pigmentation and differentiating between benign causes and those of concern. You can link to that recap here.

Plus, click here for all the Patient Care© coverage from the 2025 Midwinter Clinical Hawaii Dermatology Conference.