From the Guidelines
Ringworm (tinea corporis) should be treated with topical antifungal medications for mild to moderate cases, with first-line treatments including over-the-counter options like clotrimazole 1% cream, miconazole 2% cream, or terbinafine 1% cream, applied twice daily to the affected area and extending 1-2 cm beyond the border of the rash for 2-4 weeks. The infection is caused by dermatophyte fungi (typically Trichophyton, Microsporum, or Epidermophyton species) that feed on keratin in the skin, causing the characteristic ring-shaped, red, scaly rash with central clearing 1.
Treatment Options
- For mild to moderate cases, topical antifungal medications are recommended, with options including clotrimazole 1% cream, miconazole 2% cream, or terbinafine 1% cream, applied twice daily to the affected area and extending 1-2 cm beyond the border of the rash for 2-4 weeks.
- For more extensive or resistant infections, oral antifungal medications may be necessary, such as terbinafine 250 mg daily for 2-4 weeks, itraconazole 200 mg daily for 1-2 weeks, or fluconazole 150-300 mg weekly for 2-4 weeks 1.
- It is essential to continue treatment for at least one week after the rash resolves to prevent recurrence.
Prevention and Control
- Keep the affected area clean and dry, avoid sharing personal items, and wear loose-fitting clothing to prevent spread and recurrence.
- Avoiding skin-to-skin contact with people known to have lesions, not sharing towels and other fomites, and limiting exposure to swimming pools that have recently been associated with known outbreaks can help prevent the spread of the infection 1.
Etiology and Pathogenesis
- The infection is caused by dermatophyte fungi (typically Trichophyton, Microsporum, or Epidermophyton species) that feed on keratin in the skin, causing the characteristic ring-shaped, red, scaly rash with central clearing.
- Treatment works by disrupting the fungal cell membrane or inhibiting ergosterol synthesis, which is essential for fungal cell survival.
Note: The provided guidelines for tinea capitis 1 are not directly applicable to tinea corporis, but the general principles of treatment and prevention can be applied to both conditions.
From the FDA Drug Label
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 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. o for jock itch and ringworm: apply once a day (morning or night) for 1 week or as directed by a doctor. o wash hands after each use
The treatment for ringworm (tinea corporis) is applying terbinafine (TOP) once a day for 1 week or as directed by a doctor 2 2.
- Key points:
- Apply terbinafine (TOP) once a day
- For 1 week or as directed by a doctor
- Wash the affected skin with soap and water and dry completely before applying
- Wash hands after each use
From the Research
Ringworm Etiology and Tinea Corporis Treatment
- Ringworm, also known as tinea corporis, is a superficial fungal infection caused by dermatophytes 3
- The infection is usually diagnosed based on history and clinical appearance, plus direct microscopy of a potassium hydroxide preparation 3
Treatment Guidelines
- Topical therapy is generally successful for tinea corporis and cruris infections, unless the infection covers an extensive area or is resistant to initial therapy 3
- Treatment should continue for at least one week after clinical clearing of infection 3
- Oral antifungal agents such as fluconazole, itraconazole, and terbinafine can be effective in treating tinea corporis and cruris 4
- The efficacy of oral terbinafine versus itraconazole in treating dermatophytic infections has been compared, with itraconazole showing higher cure rates in some studies 5, 6
Dosage and Duration
- A study comparing 250 mg versus 500 mg oral terbinafine found no significant difference in efficacy between the two doses 7
- Another study found that itraconazole was more effective than terbinafine in treating tinea corporis and cruris, with a cure rate of 91.8% compared to 74.3% for terbinafine 5
- A randomized controlled trial found that itraconazole-containing groups showed significantly higher cure rates than terbinafine-only groups, with no benefit in increasing the dose or using a combination regimen 6
Clinical Considerations
- The presence of inflammation may necessitate the use of an agent with inherent anti-inflammatory properties or the use of a combination antifungal/steroid agent 3
- Treatment should be individualized based on the severity and extent of the infection, as well as the patient's medical history and other factors 3, 4, 7, 5, 6