Efficacy and safety of 250 mg versus 500 mg oral terbinafine in the treatment of tinea corporis and cruris: A randomised, assessor-blinded comparative study.

Background Though higher doses of terbinafine are often prescribed to treat dermatophyte infections, it is unknown if such doses are more effective than the conventional dose because comparative data are unavailable. Aim To compare the efficacy and safety of a once-daily dose of oral terbinafine 250 mg with 500 mg along with topical clotrimazole in the treatment of tinea infections. Methods A randomised, assessor-blinded, comparative study was carried out. Each group of subjects were administered either 250 mg or 500 mg oral terbinafine once daily for four weeks, along with topical clotrimazole. Clinical improvement was assessed after two weeks and again after four weeks from treatment initiation. Result A total of 60 patients with tinea corporis and cruris were randomised into two groups receiving either 250 mg (group A) or 500 mg (group B) oral terbinafine, along with clotrimazole cream in both groups. Baseline clinical parameters such as lesional activity (papules, vesicles and pustules), degree of erythema, scaling and severity of itching were comparable between both treatment arms. At the first and second follow-ups, no significant differences were found in the clinical parameters between the two groups. At the end of two weeks 13.8% of group A and 14.3% of group B and after 4 weeks 25.9% of group A and 33.3% of group B participants became KOH negative (P = 1.00 and 0.76, respectively). No significant difference in culture negativity was reported at the end of therapy (four weeks) between the two treatment arms (P = 0.78). Overall cure rates were 20% and 33.3% in the two treatment arms respectively at the end of the study (P = 0.82). Conclusion Oral terbinafine 250 mg daily yielded a poor cure rate in tinea cruris and corporis after 4 weeks of treatment and an increased dose of 500 mg did not have any additional benefit.