What is the treatment for fungal infection (onychomycosis or tinea pedis) of the foot?

From the Guidelines

To treat fungal infections on the foot, oral terbinafine (250mg daily for 6-12 weeks) is the recommended first-line treatment due to its higher efficacy and tolerability compared to itraconazole, as shown in a multicentre, randomized trial involving 508 subjects 1.

Treatment Options

• For mild infections, over-the-counter antifungal medications like clotrimazole (Lotrimin), miconazole (Micatin), or terbinafine (Lamisil) can be applied to the affected area twice daily for at least two weeks.
• For more severe infections, particularly those affecting the toenails, prescription-strength medications like oral terbinafine (250mg daily for 6-12 weeks) or itraconazole (200mg twice daily for one week per month, for 2-3 months) may be necessary.

Prevention and Management

• Keep feet clean and dry, change socks daily, wear breathable footwear, and avoid walking barefoot in public areas to reduce moisture around the feet and prevent recurrence.
• If the infection doesn't improve after two weeks of over-the-counter treatment, shows signs of bacterial infection (increased redness, warmth, swelling), or if you have diabetes or compromised immunity, consult a healthcare provider promptly for more aggressive treatment options.

Evidence-Based Recommendations

• The British Association of Dermatologists' guidelines for the management of onychomycosis 2014 recommend terbinafine as the first-line treatment for dermatophyte onychomycosis due to its higher efficacy and tolerability compared to itraconazole 1.
• A study published in the British Journal of Dermatology in 2003 also concludes that terbinafine is superior to itraconazole for dermatophyte onychomycosis and should be considered first-line treatment 1.

From the FDA Drug Label

Directions • adults and children 12 years and older o use the tip of the cap to break the seal and open the tube o wash the affected skin with soap and water and dry completely before applying o for athlete's foot wear well-fitting, ventilated shoes. Change shoes and socks at least once daily. ▪ between the toes only: apply twice a day (morning and night) for 1 week or as directed by a doctor. ▪ on the bottom or sides of the foot: apply twice a day (morning and night) for 2 weeks or as directed by a doctor. Uses • cures most athlete's foot (tinea pedis) • cures most jock itch (tinea cruris) and ringworm (tinea corporis) • relieves itching, burning, cracking and scaling which accompany these conditions

The treatment for fungus on foot (athlete's foot) with terbinafine (TOP) involves:

• Washing the affected skin with soap and water and drying completely before applying
• Applying the medication twice a day (morning and night) for:
  • 1 week if the fungus is between the toes
  • 2 weeks if the fungus is on the bottom or sides of the foot
• Wearing well-fitting, ventilated shoes and changing shoes and socks at least once daily 2 The medication cures most athlete's foot and relieves itching, burning, cracking, and scaling that accompany the condition 2

From the Research

Fungus on Foot Treatment Options

• Topical antifungal therapy is the mainstay of treatment for superficial or localized tinea pedis, with examples of topical antifungal agents including allylamines (e.g. terbinafine), azoles (e.g. ketoconazole), benzylamine, ciclopirox, tolnaftate, and amorolfine 3
• Oral antifungal therapy should be reserved for severe disease, failed topical antifungal therapy, concomitant presence of onychomycosis, or in immunocompromised patients, with oral antifungal agents including terbinafine, itraconazole, and fluconazole 3
• Combined therapy with topical and oral antifungals may increase the cure rate 3

Effectiveness of Different Treatments

• Terbinafine has been shown to be more effective than griseofulvin in treating tinea pedis, with a pooled risk difference of 52% in favor of terbinafine's ability to cure infection 4, 5
• Terbinafine and itraconazole have been shown to be more effective than no treatment, with terbinafine being more effective than itraconazole in some studies 4, 5, 6
• Topical terbinafine 1% cream has been shown to be significantly more effective than placebo in treating chronic tinea pedis, with 78% of patients treated with terbinafine showing combined mycologic and clinical cure at the end of therapy, compared to 0% of patients treated with placebo 7

Treatment Duration and Frequency

• Topical antifungal therapy is typically applied once to twice daily for 1-6 weeks 3
• Oral antifungal therapy is typically given for 2-6 weeks, depending on the severity of the infection and the specific medication used 3, 6