What is the treatment for tinea corporis?

Treatment of Tinea Corporis

Topical antifungal therapy is the first-line treatment for localized tinea corporis, with allylamines (terbinafine or naftifine) preferred due to shorter treatment duration of 1-2 weeks compared to azoles. 1

Topical Therapy (First-Line)

Preferred Topical Agents

• Allylamine antifungals (terbinafine, naftifine) are superior to azoles because they require only 1-2 weeks of treatment versus 2-4 weeks for azoles 1
• Terbinafine topical formulation cures most ringworm (tinea corporis) and relieves associated itching, burning, cracking, and scaling 2
• Clotrimazole 1% demonstrates significant efficacy with mycological cure rates superior to placebo (RR 2.87, NNT 2) 3

Treatment Duration

• Continue topical therapy for at least one week after clinical clearing of the infection 4
• Standard treatment duration is 2 weeks for tinea corporis 4
• If clinical improvement occurs but mycology remains positive, continue therapy for an additional 2-4 weeks 1

Oral Therapy (Second-Line)

Indications for Systemic Treatment

Oral antifungals are indicated when: 1, 5

• Infection is extensive or covers large areas
• Topical treatment has failed or infection is resistant
• Multiple lesions are present
• Patient is immunocompromised
• Infection is deep, recurrent, or chronic

Preferred Oral Regimens

• Terbinafine 250 mg daily for 1-2 weeks is particularly effective against Trichophyton tonsurans and is the preferred agent 6, 1
• Itraconazole 100 mg daily for 15 days achieves 87% mycological cure rate, superior to griseofulvin's 57% 6, 1
• Fluconazole 50-100 mg daily or 150 mg once weekly for 2-3 weeks is a third-line option with significant limitations 6, 7

Avoid Griseofulvin

• Do not use griseofulvin as first-line treatment - it requires longer duration, is less effective than terbinafine, and has lower cure rates 6

Diagnostic Confirmation

Pre-Treatment Testing

• Confirm dermatophyte infection via potassium hydroxide (KOH) preparation or fungal culture before initiating therapy 1
• Collect specimens using scalpel scraping from the active border of lesions 6
• Culture is the gold standard when diagnosis is uncertain, infection is widespread, severe, or resistant to treatment 5

Treatment Monitoring

Follow-Up Strategy

• Mycological cure, not just clinical response, is the definitive treatment endpoint 6, 1
• Follow-up with repeat mycology sampling is recommended until clearance is documented 6, 1
• Both clinical and mycological assessment should be performed at follow-up 6

Prevention of Recurrence

Essential Preventive Measures

• Screen and treat all family members, as over 50% of household contacts may be affected with anthropophilic species like T. tonsurans 6, 1
• Clean all fomites (combs, brushes, towels) with disinfectant or 2% sodium hypochlorite solution 6, 1
• Avoid skin-to-skin contact with infected individuals 6, 1
• Do not share towels, clothing, or personal items 6, 8
• Cover lesions to prevent transmission 6

Special Considerations

Combination Steroid-Antifungal Products

• Azole and steroid combination creams show slightly higher clinical cure rates at end of treatment (RR 0.67) but similar mycological cure rates compared to azoles alone 3
• Use with caution due to potential for skin atrophy and other steroid-associated complications 4
• These combinations are not currently recommended in clinical guidelines despite some evidence of benefit 3

Adverse Effects

• Topical antifungals have minimal adverse effects, mainly mild irritation and burning 3
• These effects are reported infrequently and are generally well-tolerated 3