Comparative efficacy of continuous and pulse dose terbinafine regimes in toenail dermatophytosis: A randomized double-blind trial.

INTRODUCTION: Dermatophytes are the most frequently implicated agents in toenail onychomycosis and oral terbinafine has shown the best cure rates in this condition. The pharmacokinetics of terbinafine favors its efficacy in pulse dosing. OBJECTIVES: To compare the efficacy of terbinafine in continuous and pulse dosing schedules in the treatment of toenail dermatophytosis. METHODS: Seventy-six patients of potassium hydroxide (KOH) and culture positive dermatophyte toenail onychomycosis were randomly allocated to two treatment groups receiving either continuous terbinafine 250 mg daily for 12 weeks or 3 pulses of terbinafine (each of 500 mg daily for a week) repeated every 4 weeks. Patients were followed up at 4, 8 and 12 weeks during treatment and post-treatment at 24 weeks. At each visit, a KOH mount and culture were performed. In each patient, improvement in a target nail was assessed using a clinical score; total scores for all nails and global assessments by physician and patient were also recorded. Mycological, clinical and complete cure rates, clinical effectivity and treatment failure rates were then compared. RESULTS: The declines in target nail and total scores from baseline were significant at each follow-up visit in both the treatment groups. However, the inter-group difference was statistically insignificant. The same was true for global assessment indices, clinical effectivity as well as clinical, mycological, and complete cure rates. LIMITATIONS: The short follow-up in our study may have led to lower cure rates being recorded. CONCLUSION: Terbinafine in pulse dosing is as effective as continuous dosing in the treatment of dermatophyte toenail onychomycosis.