What is the treatment for tinea corporis (ringworm) in a 17-year-old male weighing 97 kilograms (214 pounds)?

From the Guidelines

For treating ringworm in a 17-year-old male weighing 214 pounds, I strongly recommend oral terbinafine 250 mg daily for 2-4 weeks as the first-line treatment. This recommendation is based on the British Association of Dermatologists' guidelines for the management of tinea capitis 2014 1, which suggests that terbinafine is more efficacious against Trichophyton species, a common cause of ringworm. The guidelines also recommend oral therapy over topical therapy alone to achieve both clinical and mycological cure.

Key Considerations

• The patient's weight is over 40 kg, so the recommended dose of terbinafine is 250 mg per day for 2-4 weeks 1.
• Terbinafine has a shorter course of treatment compared to griseofulvin, which may increase compliance 1.
• It is essential to note that the treatment should be directed by the causative dermatophyte and/or local epidemiology, but terbinafine is a reasonable first-line choice 1.

Additional Measures

• Keep the affected areas clean and dry, wash bedding and clothing regularly in hot water, avoid sharing personal items, and wear loose-fitting clothing to reduce moisture.
• If the infection doesn't improve after two weeks of treatment, worsens, or spreads to new areas, consult a healthcare provider for further evaluation.
• In cases of treatment failure, consider lack of compliance, suboptimal absorption of the drug, relative insensitivity of the organism, and reinfection, and proceed to second-line therapy if necessary 1.

From the FDA Drug Label

Adults: 0. 5 g daily (125 mg four times a day, 250 mg twice a day, or 500 mg/day). Patients with less severe or 300 extensive infections may require less, whereas those with widespread lesions may require a starting dose of 0.75 g to 1.0 g/day. Pediatric patients (older than 2 years): A dosage of 10 mg/kg daily is usually adequate (pediatric patients from 30 to 50 lbs, 125 mg to 250 mg daily; pediatric patients over 50 lbs, 250 mg to 500 mg daily, in divided doses).

For a 17-year-old male weighing 214 pounds, the recommended dosage of griseofulvin is:

• 0.5 g daily for adults, which can be given as 125 mg four times a day, 250 mg twice a day, or 500 mg/day 2 Since the patient is over 18 years is not applicable but close to adult, and the dosage for pediatric patients over 50 lbs is 250 mg to 500 mg daily, the patient's weight is significantly higher, so the adult dosage is more applicable. Key considerations:
• The dosage should be individualized based on the severity of the infection and the patient's response to treatment.
• The patient should be diagnosed with a dermatophyte infection, and the diagnosis should be confirmed by laboratory testing before initiating treatment 2

From the Research

Treatment Options for Ringworm

• The treatment for ringworm in a 17-year-old male weighing 214 pounds can be based on several antifungal medications, including griseofulvin, terbinafine, itraconazole, and fluconazole 3, 4, 5, 6, 7.
• According to a study published in 2001, the regimens for treating tinea capitis were griseofulvin microsize 20 mg/kg/day x 6 weeks, terbinafine [> 40 kg, one 250 mg tablet; 20-40 kg, 125 mg (half of a 250 mg tablet); < 20 kg, 62.5 mg (one-quarter of a 250 mg tablet)] x 2-3 weeks, itraconazole 5 mg/kg/day x 2-3 weeks, and fluconazole 6 mg/kg/day x 2-3 weeks 3.
• A 2016 review of systemic antifungal therapy for tinea capitis in children found that terbinafine for four weeks and griseofulvin for eight weeks showed similar efficacy for the primary outcome of complete cure in children with Trichophyton species infections 4.
• Another study published in 2004 found that griseofulvin and terbinafine were effective in the treatment of tinea imbricata, with significant remission achieved in both groups lasting up to 8 weeks after cessation of therapy 5.
• A 2012 study comparing the efficacy of griseofulvin, terbinafine, and fluconazole in the treatment of tinea capitis found that griseofulvin remains the drug of choice, with cure rates of 96%, 88%, and 84% achieved with griseofulvin, terbinafine, and fluconazole, respectively 6.
• However, a 2020 study found limited effectiveness of four oral antifungal drugs (fluconazole, griseofulvin, itraconazole, and terbinafine) in the current epidemic of altered dermatophytosis in India, with itraconazole being the most effective drug 7.

Dosage and Administration

• The dosage of antifungal medications for ringworm treatment varies depending on the medication and the patient's weight 3, 4, 5, 6, 7.
• For example, the recommended dosage of terbinafine for a patient weighing over 40 kg is one 250 mg tablet per day for 2-3 weeks 3.
• The dosage of griseofulvin is typically 20 mg/kg/day for 6 weeks 3.
• Itraconazole and fluconazole dosages also vary depending on the patient's weight and the duration of treatment 3, 4, 5, 6, 7.

Efficacy and Safety

• The efficacy and safety of antifungal medications for ringworm treatment have been evaluated in several studies 3, 4, 5, 6, 7.
• Overall, the studies suggest that griseofulvin, terbinafine, itraconazole, and fluconazole are effective in treating ringworm, with varying degrees of efficacy and safety profiles 3, 4, 5, 6, 7.
• However, the 2020 study found limited effectiveness of these medications in the current epidemic of altered dermatophytosis in India, highlighting the need for further research and consideration of alternative treatment options 7.