Onychomycosis

Practice Essentials

Onychomycosis (OM) refers to a fungal infection that affects the toenails or the fingernails. It may involve any component of the nail unit, including the nail matrix, nail bed, or nail plate. (See the image below.) Although OM is not life-threatening, it can cause pain, discomfort, and disfigurement and may produce serious physical and occupational limitations. Psychosocial and emotional effects resulting from onychomycosis are widespread and may have a significant impact on quality of life.^[1]

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Proximal subungual onychomycosis. Proximal leukonychia. Image from Dr Antonella Tosti.

Signs and symptoms

Patients with OM may present with the following:

• Initially, complaints about the appearance of the nail, with no physical symptoms
• As the disease progresses, interference with standing, walking, and exercising
• Paresthesia, pain, discomfort, and loss of dexterity
• Loss of self-esteem and inhibited social interaction

OM has five main subtypes, as follows:

• Distal lateral subungual onychomycosis (DLSO)
• White superficial onychomycosis (WSO)
• Proximal subungual onychomycosis (PSO)
• Endonyx onychomycosis (EO)
• Candidal onychomycosis

Patients may have a combination of these subtypes. Total dystrophic OM, the most advanced form of any subtype, presents as a thickened, opaque, and yellow-brown nail. Presentation varies by subtype.

Features of DLSO are as follows:

• Subungual hyperkeratosis and onycholysis, which is usually yellow-white in color
• Yellow streaks and/or yellow onycholytic areas in the central portion of the nail plate

Features of WSO are as follows:

• Confined to the toenails
• Small, white, speckled or powdery patches on the surface of the nail plate
• Nail becomes roughened and crumbles easily
• Molds produce a deep variety of WSO characterized by a larger and deeper nail plate invasion

Features of PSO are as follows:

• Area of leukonychia in the proximal nail plate that moves distally with nail growth
• In PSO caused by molds, leukonychia is typically associated with marked periungual inflammation

Features of EO are as follows:

• Milky white discoloration of the nail plate
• No evidence of subungual hyperkeratosis or onycholysis

Features of candidal onychomycosis are as follows:

• Develops in patients with chronic mucocutaneous candidiasis or immunodepression
• Affects several or all digits
• Total onychomycosis associated with periungual inflammation
• Digits often take on a bulbous or drumstick appearance

See Clinical Presentation for more detail.

Diagnosis

Direct microscopy of a 20% potassium hydroxide (KOH) preparation in dimethyl sulfoxide (DMSO) can screen for fungi. The technique is as follows:

• Before obtaining a specimen, the nails must be clipped and cleansed with an alcohol swab to remove bacteria and debris
• The preparation does not require heating or prolonged incubation if DMSO is a component of the KOH solution
• In DLSO, a specimen is obtained from the nail bed by curettage; the onycholytic nail plate should be removed, and the sample should be obtained at a site most proximal to the cuticle, where the concentration of hyphae is greatest
• In PSO, the overlying nail plate must initially be pared with a No. 15 blade; then, a sample of the ventral nail plate may be taken
• In WSO, a No. 15 blade may be used to remove a specimen from the nail surface
• In suspected candidal onychomycosis, specimens should be taken from the affected nail bed closest to the proximal and lateral edges
• Nail fragments must be small enough for examination under low power
• Large pieces of nail plate may be pulverized prior to microscopy by using a hammer or a nail micronizer
• Counterstains, such as chlorazol black E or Parker blue-black ink, may be used to accentuate the hyphae

Fungal culture can identify the species of organism and guide therapy. Culture techniques are as follows:

• Two types of growth medium should be used, one for dermatophytes and one for nondermatophytes
• Medium with cycloheximide (dermatophyte test medium [DTM], Mycosel, or Mycobiotic) selects for dermatophytes
• Medium without cycloheximide (Sabouraud glucose agar, Littman oxgall medium, or inhibitory mold agar) isolates yeasts and nondermatophyte molds
• Cultures should be obtained from pulverized nail scrapings or clippings while the patient has abstained from antifungal medication for at least 2 weeks
• The specimen should be kept at room temperature with the cap placed loosely over the inoculated medium

See Workup for more detail.

Management

Medications for onychomycosis can be administered topically or orally. A combination of topical and systemic treatment increases the cure rate. Adjunctive surgical measures may also be used.

Topical therapy for onychomycosis is as follows:

• Ciclopirox olamine 8% nail lacquer solution
• Amorolfine or bifonazole/urea (available outside the United States)
• Efinaconazole 10% topical solution
• Tavaborole 0.5% topical solution, an oxaborole solution (boron-containing compound)
• Can be used in WSO and DLSO limited to the distal nail
• Should be limited to cases involving less than half of the distal nail plate or for patients unable to tolerate systemic treatment
• Topical treatments may be useful to prevent recurrence in patients cured with systemic agents

Oral therapy for onychomycosis is as follows:

• Terbinafine
• Itraconazole
• Fluconazole and posaconazole are off-label alternatives
• Systemic treatment is always required in PSO and in DLSO involving the lunula region

Nonpharmacologic approaches include the following:

• Laser treatment
• Photodynamic therapy
• Mechanical, chemical, or surgical nail avulsion
• Chemical removal with a 40-50% urea compound in patients with very thick nails
• Removal of the nail plate as an adjunct to oral therapy

Laser treatment can be combined with topical antifungals.

See Treatment and Medication for more detail.

• References

Pathophysiology

The pathogenesis of OM depends on the clinical subtype. In DLSO (the most common subtype), the fungus spreads from plantar skin and invades the nail bed via the hyponychium. Inflammation occurring in these areas of the nail apparatus causes the typical physical signs of DLSO. In contrast, WSO is a rarer presentation caused by direct invasion of the surface of the nail plate. In PSO (the least common subtype), fungi penetrate the nail matrix via the proximal nail fold and colonize the deep portion of proximal nail plate. EO is a variant of DLSO in which fungi infect the nail via the skin and directly invade the nail plate. Total dystrophic OM involves the entire nail unit. (See the image below.)

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Distal subungual onychomycosis. Onycholysis and yellow streak. Image from Dr Antonella Tosti.

Nail invasion by Candida is not common, because the yeast needs an altered immune response as a predisposing factor before it can penetrate the nails. Despite the frequent isolation of Candida from the proximal nail fold or the subungual space of patients with chronic paronychia or onycholysis, Candida is only a secondary colonizer in these patients. In chronic mucocutaneous candidiasis, the yeast infects the nail plate and eventually the proximal and lateral nail folds.

Special concerns

HIV disease

OM in patients who are immunocompromised is associated with increased severity and morbidity. Lesions may appear atypical and require more aggressive management than they would in the healthy population. Proximal subungual involvement (ie, PSO) is much more prevalent in patients with HIV infection than in those without HIV infection. In this population, WSO is more commonly caused by Trichophyton rubrum than by Trichophyton mentagrophytes.

Diabetes

The diabetic foot may lead to serious complications associated with onychomycosis.^[2] Peripheral neuropathy and sensory loss may lead to increased trauma without pain in patients with diabetes. Bacterial colonization and vascular insufficiency may exacerbate the problem and may lead to serious sequelae.

Advanced age

Onychomycosis in elderly people is complicated by diseases (eg, poor vision, arthritis) that prevent optimal foot care. Nail changes are much more common in elderly persons and often involve the fingernails and the toenails. The potential for drug-drug interactions is more evident and must be addressed before initiating oral therapy.

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Etiology

OM is caused by the following three main classes of fungi:

• Dermatophytes
• Yeasts
• Nondermatophyte molds

Dermatophytes are by far the most common cause of OM. Two major pathogens have been found to be responsible for the majority (~90%^[3] ) of OM cases: T rubrum and T mentagrophytes. In a study using data from one molecular diagnostic laboratory in the United States over the period from 2015 to 2024, T rubrum was found in 54.3% of onychomycosis specimens and T mentagrophytes in 6.5%.^[4]  However, OM caused by nondermatophyte molds (eg, Fusarium species,^[5] Scopulariopsis brevicaulis, and Aspergillus species^[4] ) is becoming more common worldwide, accounting for as many an estimated 6.9% of cases.^[6] OM due to Candida is rare.^[7]

T rubrum is the most common pathogen in DLSO. PSO due to T rubrum is typical of immunosuppressed patients. PSO with periungual inflammation is usually caused by molds. WSO is usually caused by T mentagrophytes; deep WSO is caused by nondermatophyte molds.^[8]  Mixed infections in which both T rubrum and nondermatophyte molds are present have been reported.^[9]

Candida albicans nail infection is observed in premature children, in immunocompromised patients, and in persons with chronic mucocutaneous candidiasis.

Risk factors for OM include family history, increasing age, poor health, prior trauma, warm climate, participation in fitness activities, immunosuppression (eg, HIV- or drug-induced), communal bathing, and occlusive footwear. Biomechanical problems with repetitive microtraumas to the nails cause onycholysis and other nail dystrophies that favor nail invasion by fungi.

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Epidemiology

United States and international statistics

The proliferation of fungal infections in the United States over the past few decades may be traceable to the large immigration of dermatophytes, especially T rubrum, from West Africa and Southeast Asia to North America and Europe. The incidence of OM in particular has been increasing, owing to such factors as diabetes, immunosuppression, and increasing age.

OM accounts for half of all nail disorders and is the most common nail disease in adults. Toenails are much more likely to be infected than fingernails. About 30% of patients with a cutaneous fungal infection also have OM. The global prevalence of onychomycosis has been estimated at 5.5%.^[10]

Age-, sex-, and race-related demographics

Adults are 30 times more likely to have OM than children are. OM has been reported to occur in 2.6% of children younger than 18 years but in as many as 90% of elderly people. Elderly people are more likely to have infections caused by nondermatophyte molds and yeasts.^[4] Although OM affects males more commonly than females, candidal infections and nondermatophyte mold in fections are more common in women than in men. OM affects persons of all races.

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Prognosis

The goals for antifungal therapy are mycologic cure and a normal-looking nail. Whereas mycologic cure can be evaluated at the end of treatment, assessment of clinical cure requires several more months, owing to slow nail growth.^{[11, 12]}

Yellow streaks along the lateral margin of the nail and the presence of yellow onycholytic areas in the central portion of the nail (dermatophytoma) are associated with a poor response to treatment.

Residual nail changes persist in most patients as a result of the frequent association of OM with traumatic toenail dystrophies.

OM caused by molds, particularly Fusarium species, often are not responsive to systemic therapy.^{[13, 14]}

Recurrence (relapse or reinfection) of OM is not uncommon, with reported rates in the range of 10-53%.^[12]

Fungal infections of the fingernails have a much more favorable prognosis than toenail infections.

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Patient Education

Patients should be educated about the use of appropriate footwear, especially in high-exposure areas such as communal bathing facilities and health clubs.

Following treatment, patients must be advised that nails may not appear normal for up to 1 year, and prophylactic antifungal therapy may be required to prevent reinfection of the skin and the nails. Patients may use topical terbinafine cream twice daily for 1-2 weeks for early tinea pedis or a 1-week pulse of itraconazole (200 mg PO bid) at the first signs of OM.

• References

History

Onychomycosis (OM) is usually asymptomatic; consequently, patients usually first present for cosmetic reasons, without any physical complaints.

As the disease progresses, OM may interfere with standing, walking, and exercising.

Patients may report paresthesia, pain, discomfort, and loss of dexterity. They also may report loss of self-esteem and lack of social interaction.

A careful history may reveal many environmental and occupational risk factors.

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Physical Examination

The subtypes of OM may be distinguished on the basis of their usual presenting clinical features.

In distal lateral subungual OM (DLSO), the nail shows subungual hyperkeratosis and onycholysis, which is usually yellow-white in color. Yellow streaks or yellow onycholytic areas in the central portion of the nail plate are commonly observed. (See the images below.)

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Distal subungual onychomycosis. Onycholysis and yellow streak. Image from Dr Antonella Tosti.

View Image

Distal subungual onychomycosis. Subungual hyperkeratosis onycholysis and yellow streak. Image from Dr Antonella Tosti.

Endonyx OM (EO) presents as a milky-white discoloration of the nail plate, but in contrast to DLSO, no evidence of subungual hyperkeratosis or onycholysis is present.

White superficial OM (WSO) is confined to the toenails and manifests as small, white, speckled or powdery patches on the surface of the nail plate. The nail becomes roughened and crumbles easily. Molds produce a deep variety of WSO characterized by a larger and deeper nail plate invasion. (See the image below.)

View Image

White superficial onychomycosis. Image from Dr Antonella Tosti.

Proximal subungual OM (PSO) presents as an area of leukonychia in the proximal nail plate that moves distally with nail growth. In PSO caused by molds, leukonychia is typically associated with marked periungual inflammation. (See the image below.)

View Image

Proximal subungual onychomycosis. Proximal leukonychia. Image from Dr Antonella Tosti.

Total dystrophic OM presents as a thickened, opaque, and yellow-brown nail.

In Candida OM associated with chronic mucocutaneous candidiasis or immunodepression, several or all digits are affected by total OM associated with periungual inflammation. The digits often take on a bulbous or drumstick appearance. (See the image below.)

View Image

Candidal onychomycosis in patient with chronic mucocutaneous candidiasis. Total onychomycosis and paronychia. Image from Dr Antonella Tosti.

The Onychomycosis Severity Index (OSI) was proposed as a means of grading the severity of distal subungual OM.^[15]  The OSI score is obtained by multiplying the score for the area of involvement (range, 0-5) by the score for the proximity of disease to the matrix (range, 1-5). Ten points are added for the presence of a longitudinal streaking or a patch (dermatophytoma) or for more than 2 mm of subungual hyperkeratosis. Mild OM corresponds to a score of 1-5; moderate, 6-15; and severe, 16-35.

• References

Complications

Skin injury adjacent to the nail may allow organisms to colonize, thereby increasing the risk of infectious complications. Reports of complications in elderly persons and persons with diabetes include cellulitis, osteomyelitis, sepsis, and tissue necrosis.

• References

Laboratory Studies

The clinical features of onychomycosis (OM) may mimic those of numerous other nail disorders. Therefore, laboratory diagnosis of OM must be confirmed before any treatment regimen is begun. A negative mycologic result does not rule out OM, because direct microscopy may be negative in as many as 10% of cases and culture in as many as 30%.

Direct microscopy

A 20% potassium hydroxide (KOH) preparation in dimethyl sulfoxide (DMSO) is a useful screening test for ruling out the presence of fungi. Before a specimen is obtained, the nails must be clipped and cleansed with an alcohol swab to remove bacteria and debris. The preparation does not require heating or prolonged incubation if DMSO is a component of the KOH solution.

In distal lateral subungual onychomycosis (DLSO), a specimen should be obtained from the nail bed by curettage. The onycholytic nail plate should be removed, and the sample should be obtained at a site most proximal to the cuticle, where the concentration of hyphae is greatest.

In proximal subungual onychomycosis (PSO), the overlying nail plate must initially be pared with a No. 15 blade. Then, a sample of the ventral nail plate may be taken. A No. 15 blade may also be used to remove a specimen from the nail surface in white superficial onychomycosis (WSO).

In cases of suspected candidal OM, specimens should be taken from the affected nail bed closest to the proximal and lateral edges.

Nail fragments must be small enough for examination under low power. Large pieces of nail plate may be pulverized prior to microscopy by using a hammer or a nail micronizer. Counterstains, such as chlorazol black E or Parker blue-black ink, may be used to accentuate the hyphae. Drilling to obtain specimens and taking the sample from a more proximal site may yield better results.

Culture

Direct microscopy cannot identify the specific pathogen involved in OM. A fungal culture must be obtained to identify the species of organism. Nondermatophyte molds may be resistant to the conventional therapy used for the more common dermatophytes.^[16] Therefore, two types of growth medium should be used: one with cycloheximide (dermatophyte test medium [DTM], Mycosel, or Mycobiotic) to select for dermatophytes and one without cycloheximide (Sabouraud glucose agar, Littman oxgall medium, or inhibitory mold agar) to isolate yeasts and nondermatophyte molds.

Cultures should be obtained from pulverized nail scrapings or clippings while the patient has abstained from antifungal medication for at least 2 weeks. The specimen should be kept at room temperature with the cap placed loosely over the inoculated medium.

• References

Other Tests

Polymerase chain reaction (PCR) assays have been developed to detect fungal DNA from infected nails. A highly sensitive nested PCR assay using species-specific primer pairs based on the 28S ribosomal RNA gene has been developed.^[7] This methodology permits detection of both dermatophytes and nondermatophytes.^[17]

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Procedures

Dermoscopy (dermatoscopy) is useful for distinguishing distal subungual OM from traumatic onycholysis. In distal subungual OM, the proximal border of the onycholytic area is jagged, owing to the presence of yellow-white spikes that project into the proximal nail plate. (See the image below.) This has been reported as the "aurora borealis" pattern.^[18] Dermoscopy may be best used as a complement to culture and PCR assay or as a means of screening for laporatory sampling.^[19]

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Dermoscopy of distal subungual onychomycosis showing irregular margin of onycholytic area with spikes projecting into proximal nail plate, reported as....

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Histologic Findings

Histologic examination of the nail is a highly useful alternative to culture or KOH testing. Nail clippings may be sent to the laboratory for diagnosis in a formalin-filled container, or, as a last resort, an incisional nail biopsy (by punch or scalpel) may be performed to help confirm the diagnosis.

Staining in the laboratory should be performed with periodic acid-Schiff (PAS) stain or methenamine silver stain to reveal fungal elements. A meta-analysis comparing three methods of diagnosing onychomycosis found that nail biopsy with PAS staining was more efficient and accurate than cultire or KOH examination.^[20] Examining formalin-fixed PAS-stained specimens has a higher probability (a higher negative predictive value) than KOH examination in determining that a patient is disease-free if the test results are negative.

In addition to excluding other conditions (eg, psoriasis, lichen planus), the topographic distribution, the density, and the nature of the fungal elements may help guide treatment. Biopsy specimens of onychomycosis may show features of psoriasiform hyperplasia, including parakeratosis, thinned rete ridges, narrow suprapapillary plates, and dilated tortuous capillaries. Like direct microscopy, histopathologic diagnosis does not identify the species of the causative pathogen.

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Medical Care

Treatment of onychomycosis (OM) depends on the clinical subtype, the number of affected nails, and the severity of nail involvement.^{[21, 22, 23, 24, 25]}

A systemic treatment is always required in proximal subungual OM (PSO) and in distal lateral subungual OM (DLSO) involving the lunula region. White superficial OM (WSO) and DLSO limited to the distal nail can be treated with a topical agent. A combination of systemic and topical treatment increases the cure rate. Because the rate of recurrence remains high, even with newer agents, the decision to treat should be made with a clear understanding of the cost and risks involved, as well as the risk of recurrence.^[22]

Photodynamic therapy and lasers may represent future treatment options.^[26]

Topical antifungals

The use of topical agents should be limited to cases involving less than half of the distal nail plate or cases in which patients are unable to tolerate systemic treatment. Agents available in the United States include ciclopirox olamine 8% and efinaconazole 10% nail solutions. Amorolfine and bifonazole/urea are available outside the United States.

Topical treatments alone generally cannot cure onychomycosis, because of insufficient nail plate penetration.^[27] Ciclopirox and amorolfine solutions have been reported to penetrate through all nail layers but have low efficacy when used as monotherapy. They may be useful as adjunctive therapy in combination with oral therapy or as prophylaxis to prevent recurrence in patients cured with systemic agents. Daily application and a long duration of treatment (48 wk) are required for efinaconazole and ciclopirox.^{[28, 29]}

Efinaconazole is indicated for toenail onychomycosis. Its approval was based on two phase III multicenter, randomized trials (N = 1655), in which complete cure was seen in 17.8% and 15.2% of patients receiving the drug vs 3.3% and 5.5% of subjects receiving the vehicle.^[30] Mycologic cure rates were significantly greater with efinaconazole (53.4-55.2%) than with the drug vehicle. Data indicate that efinaconazole is very effective in the treatment of yellow streaks and dermathophytoma, which are often resistant to oral antifungals.^[31]

Tavaborole, a topical oxaborole (boron-containing) antifungal, is indicated for onychomycosis of the toenails due to T rubrum or T mentagrophytes. Its approval was based on two multicenter, double-blind, randomized trials involving 1194 subjects.^[32] After 48 weeks of treatment, complete cure was found in 6.5% and 9.1% in patients receiving tavaborole compared with 0.5% and 1.5%, respectively, of patients applying the vehicle alone. Mycologic cure was obtained in 31.1% and 35.9% for active treatment vs  7.2% and 12.2% for the vehicle.

Laser treatment can be combined with topical antifungals.^{[33, 34]}

Oral therapy

The newer generation of oral antifungal agents (itraconazole and terbinafine) has replaced older therapies in the treatment of onychomycosis.^[35] They offer shorter treatment regimens, higher cure rates, and fewer adverse effects. The efficacy of the newer antifungal agents lies in their ability to penetrate the nail plate within days of starting therapy. In the past few years, however, reports of resistance to terbinafine have been growing in number worldwide.^[36]  It is therefore very important to refrain from starting oral treatment without mycologic confirmation of the diagnosis and to consider resistance when treatment is ineffective.

Fluconazole and posaconazole^[37]  (neither approved by the US Food and Drug Administration [FDA] for treatment of onychomycosis as of November 2024) may be alternatives to itraconazole and terbinafine. Other azoles that have not yet been approved for this indication include voriconazole and fosravuconazole.^[35]

Various clinical trials have demonstrated higher efficacy for terbinafine than for other antifungal treatments.^{[38, 39, 40, 41]}  A meta-analysis of 18 studies on terbinafine, six studies on pulse itraconazole, and three studies on fluconazole for onychomycosis showed mycologic cure rates of 76%, 63%, and 48% respectively.^[42]

To decrease the adverse effects and duration of oral therapy, topical treatments and nail avulsion may be combined with oral antifungal management.^[43]

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Surgical Care

Several laser devices have been used to treat onychomycosis, including Nd:YAG lasers and carbon dioxide lasers.^[44]  Some data suggest that laser therapy may be as effective as terbinafine, with fewer adverse effects, but there remains a need for more data from large-scale randomized controlled trials.^[45] Laser treatment can be combined with topical antifungals.^{[33, 34]}

Photodynamic therapy has been reported as effective in noncontrolled studies^{[46, 47]} ; more research is needed.

Surgical approaches to onychomycosis treatment can also include mechanical, chemical, or surgical nail avulsion. Chemical removal by using a 40-50% urea compound is painless and useful in patients with very thick nails. Removal of the nail plate should be considered an adjunctive treatment in patients undergoing oral therapy. A combination of oral, topical, and surgical therapy can increase efficacy and reduce cost.

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Activity

Activity does not need to be limited during treatment, but patients should be educated about avoiding direct contact with high-risk areas in public places.

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Long-Term Monitoring

Although hepatotoxic reactions are unlikely, periodic monitoring of patients undergoing oral antifungal therapy should include a complete blood count (CBC) and measurements of liver enzyme levels approximately every 4-6 weeks.

Treatment may be discontinued after standard dosing with terbinafine or itraconazole when no evidence of fungal infection (by microscopy or culture) is present. Nails may continue to look dystrophic after a cure is achieved in the laboratory.

After antifungal therapy, disease-free nail growth should be measured at every visit. Nails should grow at a rate of 1.5-2 mm per month and may take as long as 1 year to look normal. A clinician may consider an additional dose of antifungal medication if the outgrowth distance slows or stops after discontinuance of therapy.

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Guidelines Summary

In 2014, the British Association of Dermatologists published updated evidence-based guidelines for the management of onychomycosis.^[25] Treatment recommendations are given for both adults and children (aged 1-12 y).

Systemic treatment recommendations for adults are as follows:

• Terbinafine as first line of treatment for dermatophyte onychomycosis and generally preferred over itraconazole; not recommended for patients with active or chronic liver disease (level A)
• Itraconazole as first line of treatment for dermatophyte onychomycosis (level A)
• Fluconazole may be a useful alternative in patients unable to tolerate terbinafine or itraconazole (level B)
• Griseofulvin is no longer a treatment of choice owing to lower efficacy and higher relapse rates compared with terbinafine and itraconazole (level C)
• Combination treatment recommended if response to topical monotherapy is likely to be poor (level D)

Topical treatment recommendations for adults are as follows:

• Amorolfine or tioconazole are useful for superficial and distal onychomycosis (level D)
• Ciclopirox is useful for superficial and distal onychomycosis and for patients in whom systemic therapy is contraindicated (level D)

Other treatment recommendations for adults are as follows:

• Surgical avulsion, debridement alone, and photodynamic therapy (PDT) not recommended

Systemic treatment recommendations for children are as follows:

• Terbinafine as first line of treatment for dermatophyte onychomycosis and generally preferred over itraconazole (level A)
• Itraconazole is first line of treatment for dermatophyte onychomycosis (level A)
• Fluconazole considered as second line if itraconazole and terbinafine contraindicated or not tolerated (level B)
• Griseofulvin considered as second line if itraconazole and terbinafine contraindicated or not tolerated (level C)

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Terbinafine (Lamisil)

• Dosing, Interactions, etc.

Clinical Context: 

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Itraconazole (Onmel, Sporanox, Sporanox Oral Solution)

• Dosing, Interactions, etc.

Clinical Context: 

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Fluconazole (Diflucan)

• Dosing, Interactions, etc.

Clinical Context: 

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Ciclopirox (Loprox, Penlac)

• Dosing, Interactions, etc.

Clinical Context: 

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Efinaconazole (Jublia)

• Dosing, Interactions, etc.

Clinical Context: 

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Tavaborole (Kerydin)

• Dosing, Interactions, etc.

Clinical Context: 

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