What is the preferred treatment, fluconazole (antifungal medication) or griseofulvin (antifungal medication), for a patient with tinea corporis (ringworm of the body)?

Treatment Recommendation for Tinea Corporis

For tinea corporis, topical antifungal therapy is first-line treatment for localized disease, but when oral therapy is needed, neither fluconazole nor griseofulvin should be your first choice—itraconazole or terbinafine are superior options based on efficacy data. 1, 2

When Oral Therapy is Indicated

Oral antifungals are reserved for specific situations rather than routine tinea corporis 1:

• Extensive infections covering large body surface areas
• Treatment failures with topical therapy
• Immunocompromised patients
• Patients unable to apply topical medications consistently

Comparative Efficacy: The Evidence

Itraconazole vs Griseofulvin

Itraconazole demonstrates clear superiority over griseofulvin with a mycological cure rate of 87% compared to griseofulvin's 57% when both are given for 15 days 3, 4. This represents a 30% absolute improvement in cure rates, which is clinically significant for patient outcomes 4.

In head-to-head trials, itraconazole 100 mg daily for 15 days achieved:

• 87% mycological cure vs. 57% with griseofulvin 4
• 91% clinical response at follow-up vs. 64% with griseofulvin 4
• Better tolerability profile 4

Fluconazole Performance

Fluconazole 150 mg once weekly for 2-4 weeks shows efficacy in tinea corporis, reducing clinical severity scores from 7.1 to 1.5 (p=0.001) 5. However, no direct comparative trials exist between fluconazole and griseofulvin specifically for tinea corporis, making evidence-based comparison impossible 5.

The British Association of Dermatologists guidelines note that fluconazole has been used for tinea capitis but "its use has been relatively limited because of side-effects and because it confers no cost advantage" 6. This same limitation applies to tinea corporis 6.

Terbinafine: The Preferred Option

Terbinafine 250 mg daily for 1-2 weeks achieves >80% mycological cure rates in tinea corporis/cruris and is particularly effective against Trichophyton rubrum and T. mentagrophytes, the most common causative organisms 1, 7. Terbinafine offers:

• Shorter treatment duration (1-2 weeks vs. 2-4 weeks for griseofulvin) 1, 8
• Superior efficacy compared to griseofulvin in comparative trials 7
• Fungicidal mechanism with residual tissue effect 7
• Minimal drug-drug interactions compared to azoles 1

Practical Treatment Algorithm

Step 1: Confirm diagnosis via KOH preparation or fungal culture before initiating therapy 1, 2

Step 2: Assess disease extent:

• Localized disease → Topical terbinafine 1% daily for 1-2 weeks 1
• Extensive disease, treatment failure, or immunocompromised → Proceed to oral therapy

Step 3: Select oral agent based on this hierarchy:

1. First choice: Terbinafine 250 mg daily for 1-2 weeks 1, 2
2. Second choice: Itraconazole 100 mg daily for 15 days 2, 4
3. Third choice: Fluconazole 150 mg weekly for 2-4 weeks (if azole preferred and itraconazole unavailable) 5
4. Last resort: Griseofulvin 500 mg daily for 2-4 weeks (only if all other options contraindicated) 8

Critical Monitoring Considerations

Mycological cure, not clinical improvement, is the definitive treatment endpoint 1, 2. This is a common pitfall—patients may appear clinically improved while still harboring viable dermatophytes 2.

• Repeat mycology sampling at end of treatment 2
• If clinical improvement occurs but mycology remains positive, continue therapy for additional 2-4 weeks 1
• If no initial clinical improvement, switch to alternative agent 2

Important Safety Considerations

Terbinafine

• Contraindicated in active/chronic liver disease and lupus erythematosus 1
• Baseline liver function tests recommended 2
• Gastrointestinal disturbances occur in 49% (usually mild) 1
• Serious adverse events rare (0.04% incidence) 1

Itraconazole

• Contraindicated in heart failure 2
• Significant drug interactions with warfarin, certain antihistamines (terfenadine, astemizole), antipsychotics, midazolam, digoxin, and simvastatin 6, 2
• Monitor liver function with prolonged therapy 2

Griseofulvin

• Contraindicated in lupus erythematosus, porphyria, and severe liver disease 6
• Requires 2-4 weeks treatment duration 8
• Must be continued until organism completely eradicated 8
• Drug interactions with rifampicin (decreased levels) and cimetidine (increased levels) 6

Prevention of Recurrence

Screen and treat household contacts, as >50% may be affected with anthropophilic species 1:

• Clean all fomites (towels, clothing) with disinfectant or 2% sodium hypochlorite 1
• Avoid skin-to-skin contact with infected individuals 1
• Do not share towels or personal items 1