What is the recommended treatment for tinea (ringworm)?

Treatment of Tinea (Ringworm)

Terbinafine 1% cream applied once daily for 1-2 weeks is the recommended first-line treatment for tinea corporis (ringworm). 1

Diagnosis Before Treatment

Before initiating treatment, proper diagnosis is essential:

• Confirm diagnosis through microscopic examination (KOH preparation) or fungal culture, especially for stubborn cases 1
• Treatment can be initiated while awaiting confirmatory mycology if clinical signs are present (scale, lymphadenopathy, alopecia, kerion) 1
• Accurate identification of the infecting organism is crucial for selecting appropriate treatment 2

Treatment Algorithm

1. Topical Treatment (First-Line)

• For localized tinea corporis:
  • Terbinafine 1% cream once daily for 1-2 weeks 1
  • Alternative options: clotrimazole 1% cream or miconazole 2% cream twice daily for 2 weeks 1
  • Continue treatment for at least one week after clinical resolution 1, 3

2. Systemic Treatment (For Extensive or Resistant Cases)

• For extensive or resistant tinea corporis:
  • Oral itraconazole 5 mg/kg/day (or 100-200 mg daily for adults) for 2-4 weeks 1
  • Oral terbinafine 250mg daily for 1-2 weeks (especially for Trichophyton species) 1
  • Oral griseofulvin 0.5g daily for adults (10 mg/kg daily for children) for 2-4 weeks 1, 2

Evidence Strength and Treatment Selection

Terbinafine has demonstrated superior efficacy in clinical trials:

• Terbinafine 1% cream applied twice daily for 1 week showed significantly higher cure rates (93.5%) compared to clotrimazole 1% cream applied for 4 weeks (73.1%) 4
• Even once-daily application of terbinafine for 7 days achieved 84.2% mycological cure rate in tinea corporis/cruris 5

The FDA label for griseofulvin indicates it should be used for 2-4 weeks for tinea corporis, with dosage individualized based on severity 2. However, the most recent guidelines favor terbinafine as first-line therapy due to its superior efficacy and shorter treatment duration 1.

Special Considerations

• Treatment duration: Continue until mycological cure is achieved, typically 1-2 weeks after clinical improvement 1, 2
• Monitoring: Follow-up mycological examination is recommended until clearance is achieved, especially in resistant cases 1
• Safety profiles:
  • Terbinafine: Generally well-tolerated; rare serious reactions include Stevens-Johnson syndrome and hepatic toxicity 1
  • Itraconazole: Primarily gastrointestinal side effects, cutaneous eruptions, occasional headache 1
  • Griseofulvin: Generally well-tolerated; side effects include gastrointestinal disturbances and rashes in <8% of patients 1

Prevention of Reinfection

• Screen and treat all household members for anthropophilic infections 1
• Cleanse personal items with disinfectant and avoid sharing them 1
• Apply antifungal powders containing miconazole or clotrimazole to prevent reinfection 1
• For footwear-related infections, consider discarding heavily contaminated footwear and using antifungal powders inside shoes 1

Common Pitfalls to Avoid

• Premature discontinuation: Patients often stop treatment when symptoms improve, leading to incomplete cure and recurrence 6
• Misdiagnosis: Differential diagnosis between tinea corporis and conditions like pityriasis rosea is crucial, as they require different treatments 1
• Inadequate treatment duration: Treatment should continue for at least one week after clinical resolution to ensure mycological cure 1, 3
• Failure to address reinfection sources: Not addressing potential sources of reinfection can lead to treatment failure 1, 2