What is the recommended treatment for ringworm?

Treatment of Ringworm

For ringworm (tinea corporis/cruris), topical antifungal agents are the first-line treatment for localized infections, while oral antifungals are recommended for extensive, severe, or resistant cases.

Diagnosis

• Confirm diagnosis through direct microscopic examination using potassium hydroxide (KOH) preparation or culture on appropriate medium 1
• Characteristic clinical appearance includes circular, scaly patches with central clearing and raised borders

Treatment Algorithm

First-Line Treatment: Topical Antifungals

For localized, uncomplicated tinea corporis/cruris:

• Azoles (clotrimazole 1%, miconazole, ketoconazole)

  • Apply twice daily for 2-4 weeks 2
  • Continue treatment for at least 1 week after clinical resolution

• Allylamines (terbinafine 1%, naftifine 1%)

  • Apply once or twice daily for 1-2 weeks 2
  • More effective than placebo with NNT of 3 for clinical cure 2

Second-Line Treatment: Oral Antifungals

For extensive, severe, inflammatory, or resistant infections:

• Terbinafine

  • 250 mg daily for 1-2 weeks 3
  • Highly effective for dermatophyte infections

• Fluconazole

  • 150 mg once weekly for 2-3 weeks, or
  • 50-100 mg daily for 2-3 weeks 3

• Itraconazole

  • 100 mg daily for 2 weeks, or
  • 200 mg daily for 7 days 3

• Griseofulvin

  • Adults: 500 mg daily (or 250 mg twice daily) for 2-4 weeks 1
  • Children: 10 mg/kg daily in divided doses 1
  • Historically used but superseded by newer agents 4

Special Considerations

Treatment Duration

• Continue medication until the infecting organism is completely eradicated as indicated by clinical or laboratory examination 1
• Typical treatment periods for tinea corporis: 2-4 weeks 1

Adjunctive Measures

• Implement general hygiene measures to control sources of infection or reinfection 1
• Keep affected areas clean and dry
• Avoid sharing personal items (towels, clothing, etc.)
• Wash clothing, bedding, and towels in hot water

Monitoring and Follow-up

• Clinical improvement should be seen within 1-2 weeks of starting treatment
• Complete resolution typically occurs within 4 weeks
• If no improvement after 2 weeks of appropriate therapy, reassess diagnosis

Treatment Failures

• Consider non-compliance with treatment regimen
• Possibility of resistant organism
• Misdiagnosis (could be another condition like eczema or psoriasis)
• Immunocompromised state

Special Populations

Athletes/Contact Sports Players

• May require longer treatment duration (2-3 months) with oral antifungals 5
• More aggressive treatment may be needed due to increased risk of transmission and reinfection

Children

• Griseofulvin: 10 mg/kg daily for children over 2 years 1
• Terbinafine and itraconazole are alternatives but may be used off-label in younger children

Common Pitfalls

1. Inadequate treatment duration leading to recurrence
2. Failure to identify and treat all infected body sites
3. Not addressing potential sources of reinfection (clothing, bedding, family members, pets)
4. Misdiagnosis of other annular skin conditions as ringworm
5. Inappropriate use of combination antifungal-steroid preparations, which can worsen infection

Remember that proper diagnosis is essential before initiating treatment, and general hygiene measures are crucial to prevent reinfection or spread to others.