Medication Summary
Tinea pedis can be treated with topical or oral antifungals or a combination of both. [15, 16, 17] Topical agents are used for 1-6 weeks, depending on manufacturers' recommendations. Luliconazole, an imidazole topical cream, is applied once daily for 2 weeks. [18, 19] A patient with chronic hyperkeratotic (moccasin) tinea pedis should be instructed to apply medication to the bottoms and sides of his or her feet. For interdigital tinea pedis, even though symptoms may not be present, a patient should apply the topical agent to the interdigital areas and to the soles because of the likelihood of plantar-surface infection.
Naftifine gel or cream 2% is indicated for interdigital tinea pedis in adults and adolescents. A study using 2% gel for interdigital-type tinea pedis demonstrated greater improvement from baseline for complete cure (P = .001), mycological cure (P< .0001), and treatment effectiveness (P< .0001) as early as 2 weeks when compared with vehicle; however the highest response rates were seen 4 weeks post treatment (P< .0001, for all endpoints). Statistically significant results for complete cure, mycological cure, and treatment effectiveness (P< .0001, for all endpoints) were also seen at week 6 among subjects with moccasin-type tinea pedis. [20]
Recurrence of tinea pedis is often due to a patient's discontinuance of medication after symptoms abate. A simple strategy to increase a patient's compliance is to prescribe a large quantity of topical medicine, which may motivate a patient to continue use until the entire tube is empty.
Moccasin-type tinea pedis is often recalcitrant to topical antifungals alone, owing to the thickness of the scale on the plantar surface. The concomitant use of topical urea or other keratolytics with topical antifungals should improve the response to topical agents. [21] In addition, for moccasin tinea pedis caused by Scytalidium species, Whitfield solution, containing benzoic and salicylic acids, can be beneficial. However, patients with extensive chronic hyperkeratotic tinea pedis or inflammatory/vesicular tinea pedis usually require oral therapy, as do patients with concomitant onychomycosis, [22] diabetes, [23] peripheral vascular disease, or immunocompromising conditions.
An econazole foam is now available. [24]
Topical benzylamines have been shown to be effective in some patients with interdigital tinea pedis with only 1 week of treatment. [25]
Regarding itraconazole, there may be some advantage to giving itraconazole with whole milk to increase absorption. [26] However, because of its metabolism, drug interactions with inhibitors of cytochrome P450 are possible. [27]
Terbinafine-resistant strains have been described. [28]
Topical imidazoles
Class Summary
Topical imidazoles are effective in all forms of tinea pedis but are excellent treatments for interdigital tinea pedis because they are effective against dermatophytes and Candida. Some of these drugs (eg, econazole) also have antibacterial activity. An econazole foam is now available.
Clotrimazole 1% (Mycelex, Lotrimin)
Clotrimazole is a broad-spectrum antifungal agent that inhibits yeast growth by altering cell-membrane permeability, causing death of fungal cells. Reevaluate the diagnosis if no clinical improvement occurs after 4 weeks.
Econazole topical (Ecoza)
Econazole is effective in cutaneous infections. It may interfere with RNA and protein synthesis and metabolism. Econazole disrupts cell membrane permeability, causing death of fungal cells.
Ketoconazole topical (Nizoral)
Ketoconazole is an imidazole broad-spectrum antifungal agent; it inhibits the synthesis of ergosterol, causing cellular components to leak, resulting in death of fungal cells.
Miconazole topical (Monistat)
Miconazole damages the fungal cell wall membrane by inhibiting the biosynthesis of ergosterol. Membrane permeability is increased, causing nutrients to leak out, resulting in fungal cell death. The 2% lotion is preferred in intertriginous areas. If the 2% cream is used, apply sparingly to avoid maceration effects.
Oxiconazole 1% cream (Oxistat)
Oxiconazole damages the fungal cell wall membrane by inhibiting the biosynthesis of ergosterol. Membrane permeability is increased, causing nutrients to leak out, resulting in death of fungal cells.
Sertaconazole nitrate cream (Ertaczo)
Sertaconazole nitrate is a topical imidazole antifungal active against T rubrum, T mentagrophytes, and E floccosum. It is indicated for tinea pedis.
Luliconazole (Luzu)
Luliconazole is an imidazole antifungal that alters the fungal cell membrane by interacting with 14-alpha demethylase (an enzyme necessary for conversion of lanosterol to ergosterol). It is indicated for interdigital tinea pedis caused by the organisms Trichophyton rubrum and Epidermophyton floccosum in adults and children aged 12 years or older. It is available as a 1% topical cream.
Topical pyridones
Class Summary
Topical pyridones are broad-spectrum agents with antidermatophytic, antibacterial, and anticandidal activity and are therefore useful in all forms of tinea pedis but especially effective in interdigital tinea pedis.
Ciclopirox 1% cream (Loprox)
Ciclopirox interferes with the synthesis of DNA, RNA, and protein by inhibiting the transport of essential elements in fungal cells.
Topical allylamines
Class Summary
Topical allylamines are effective in treating all forms of tinea pedis. In vitro, these agents have demonstrated potent activity against dermatophyte fungi, so they are useful in treating patients with refractory tinea pedis (eg, chronic hyperkeratotic). Terbinafine 1% (Lamisil) has been shown to be effective in some patients with interdigital tinea pedis with only 1 week of treatment. Patients with chronic hyperkeratotic tinea pedis generally require 4 weeks of treatment.
Naftifine (Naftin)
Naftifine is a broad-spectrum antifungal agent and synthetic allylamine derivative. Naftifine interferes with sterol biosynthesis in the fungal cell wall by inhibiting squalene monooxygenase (squalene 2,3-epoxidase). It is indicated for tinea pedis caused by the organism Trichophyton rubrum. Use the 1% cream or gel in adults for tinea pedis (twice daily for 4 wk) or the 2% cream or gel in adolescents and adults with interdigital tinea pedis (once daily for 2 wk).
Terbinafine topical (Lamisil)
Terbinafine inhibits squalene epoxidase, which decreases ergosterol synthesis, causing death of fungal cells. Use it until symptoms significantly improve. The duration of treatment should be longer than 1 week but not longer than 4 weeks. Terbinafine-resistant strains have been described.
Topical benzylamines
Class Summary
Topical benzylamines are sometimes classified as a subset of allylamines. They are useful for treating patients with refractory tinea pedis (eg, chronic hyperkeratotic). Topical benzylamines have been shown to be effective in some patients with interdigital tinea pedis with only 1 week of treatment.
Butenafine (Mentax)
Butenafine damages fungal cell membranes, arresting the growth of fungal cells.
Oral antimycotics
Class Summary
Oral antimycotics should be considered in patients with extensive chronic hyperkeratotic or inflammatory/vesicular tinea pedis. They could also be used for patients with disabling disease, patients in whom topical treatments have failed, patients with diabetes or peripheral vascular disease, and patients with immunocompromising conditions.
There may be some advantage to giving itraconazole with whole milk to increase absorption.
Itraconazole (Sporanox)
Itraconazole has fungistatic activity. It is a synthetic triazole antifungal agent that slows fungal cell growth by inhibiting cytochrome P-450–dependent synthesis of ergosterol, a vital component of fungal cell membranes.
Terbinafine (Lamisil, Daskil)
Terbinafine inhibits squalene epoxidase, which decreases ergosterol synthesis, causing the death of fungal cells. Use it until symptoms significantly improve.
Fluconazole (Diflucan)
Fluconazole is a synthetic oral antifungal (broad-spectrum bistriazole) that selectively inhibits fungal cytochrome P-450 and sterol C-14 alpha-demethylation.
Dermatological agents
Class Summary
These dermatological agents may be used to supplement antimycotic agents in certain clinical situations.
Aluminum acetate solution (Domeboro Astringent Solution Powder Packets, Gordon's Boro-Packs, Pedi-Boro Soak Paks)
Aluminum acetate is a drying agent for vesicular tinea pedis. Dissolve aluminum acetate tablets in water to produce a 1:10-40 solution.
Ammonium lactate lotion (Lac Hydrin)
Ammonium lactate lotion is used to decrease scaling in patients with hyperkeratotic soles. It contains lactic acid, an alpha hydroxy acid that has keratolytic action and thus facilitates release of comedones. It causes disadhesion of corneocytes. Ammonium lactate lotion is available in 12% and 5% strengths. Use 12% lotion.
Urea, topical (Carmol-40, Keralac)
Topical urea is esed to decrease scaling in patients with hyperkeratotic soles. It promotes hydration and removal of excess keratin by dissolving the intracellular matrix. It is available in 10-40% concentrations.
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Tinea pedis lesion. Image courtesy of Drgnu23 (original uploader) [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0/)], via Wikimedia Commons.
