What is the treatment for ringworm?

Treatment of Ringworm (Dermatophyte Infections)

For localized tinea corporis or tinea cruris, topical antifungal therapy with terbinafine, naftifine, or azoles (clotrimazole, miconazole) applied once or twice daily for 2-4 weeks is the first-line treatment, while extensive disease, scalp involvement (tinea capitis), or nail infections (tinea unguium) require oral antifungal therapy with terbinafine as the preferred agent. 1

Diagnostic Confirmation Required

• Confirm the diagnosis before initiating treatment through KOH preparation, fungal culture, or nail biopsy to identify dermatophyte infection 2, 1
• Clinical diagnosis alone is unreliable—tinea corporis mimics eczema, and onychomycosis resembles dystrophic nails from trauma or psoriasis 1

Treatment Algorithm by Site and Severity

Localized Tinea Corporis (Body) and Tinea Cruris (Groin)

Topical therapy is first-line:

• Terbinafine cream applied once or twice daily for 2-4 weeks provides superior efficacy (NNT 3 for clinical cure vs placebo) 3
• Naftifine 1% is highly effective (NNT 3 for mycological cure) 3
• Azoles (clotrimazole 1%, miconazole) applied twice daily for 2-4 weeks are effective alternatives (NNT 2 for mycological cure with clotrimazole) 3
• Treatment duration: tinea corporis 2-4 weeks 2, 4

Oral therapy indicated when:

• Extensive or chronic involvement 1, 5
• Failure of topical treatment 1
• Hair follicle involvement 1
• Immunocompromised patients 1

Oral regimens:

• Terbinafine 250 mg daily for 1-2 weeks 4
• Itraconazole 100 mg daily for 2 weeks or 200 mg daily for 7 days 4
• Fluconazole 50-100 mg daily for 2-3 weeks or 150 mg once weekly 4

Tinea Pedis (Foot)

Topical therapy:

• Apply topical antifungals once or twice daily for 4-8 weeks 2, 1
• Terbinafine or azoles are effective 3
• Concomitant topical therapy is usually required even with oral treatment 2

Oral therapy for extensive/chronic disease:

• Terbinafine 250 mg daily for 2 weeks 4
• Itraconazole 100 mg daily for 2 weeks or 400 mg daily for 1 week 4
• Fluconazole 150 mg once weekly (pulse dosing) 4

Tinea Capitis (Scalp)

Oral therapy is mandatory—topical agents are ineffective:

• Terbinafine is first-line due to efficacy, tolerability, and cost 1
• Griseofulvin (only FDA-approved agent for pediatric tinea capitis): 2
  • Adults: 500 mg daily (can start 750 mg-1 g daily for extensive disease)
  • Children >2 years: 10 mg/kg daily (typically 125-500 mg daily based on weight)
  • Duration: 4-6 weeks minimum 2
• Alternative agents (itraconazole, fluconazole) offer shorter treatment intervals with acceptable safety profiles 6
• Systemic therapy prevents disfiguring hair loss, permanent scarring, and transmission to others 6

Tinea Unguium/Onychomycosis (Nails)

Oral therapy is primary treatment:

• Terbinafine is first-line for onychomycosis 1, 5
• Treatment duration depends on growth rate: 2
  • Fingernails: minimum 4 months
  • Toenails: minimum 6 months
• Topical amorolfine or ciclopirox may be used for milder cases 5

Critical Management Points

General Hygiene Measures

• Implement hygiene measures to control infection sources and prevent reinfection 2
• Educate patients on proper foot hygiene to reduce relapse risk 5

Treatment Duration and Follow-up

• Continue medication until complete eradication of the organism as confirmed by clinical or laboratory examination 2
• Clinical relapse occurs if treatment is stopped prematurely 2
• Relapse remains problematic, particularly with tinea pedis and onychomycosis 5

Important Caveats

Avoid combination antifungal-corticosteroid products:

• While azole-steroid combinations show higher clinical cure rates at end of treatment, they are not recommended in clinical guidelines 3
• Antifungal stewardship should be emphasized to prevent resistance 1

Griseofulvin is ineffective against:

• Candidiasis, bacterial infections, and other fungal infections (histoplasmosis, blastomycosis, etc.) 2
• Yeasts and bacteria that may coexist with dermatophytes in tinea pedis 2

Emerging resistant tinea infections:

• May be more severe than classic infections 1
• Generally do not respond to first-line topical or oral antifungals 1
• May require prolonged oral therapy and specialized diagnostic testing 1

Adverse Effects

• All topical and oral antifungals examined have minimal adverse effects, mainly irritation and burning with topical agents 3
• Oral agents (terbinafine, itraconazole, fluconazole) have adverse effects and drug interactions within acceptable limits 6