Terbinafine hydrochloride treatment of Microsporum canis experimentally-induced ringworm in cats

Cats represent the most important source of Microsporum canis infection to people. Terbinafine hydrochloride is commonly used in the treatment of micr osporosis. Its fungicidal action permits short period of treatment. It was our objective to evaluate the effectiveness of this drug in treatment of mi crosporosis in cats. We treated nine experimentally U. canis infected cats with terbinafine at a dose of 10-20 mg/kg SID (low-dose group, LDG), nine cats with 30-40 mg/kg SID (high-dose group, HDG), and nine cats were left untreated (control grou p, CG). The drug's levels in cats' plasma and hair were measured by a rever sed-phase high performance liquid chromatographic method (RP-HPLC) and the cats' cure was followed by Wood's lamp illumination, microscopic exam and f un.-al culture. We showed no difference between the clinical course in CG and LDG, but HDG were significantly differentiated from both other groups. Terbinafine level s in plasma at 120 days of treatment were not statistically different among LDG (4.13 mug/l) and HDG (5.48 mug/l), but levels in hair of LDG (1.24 mug /l) and HDG (3.62 mug/l) were significantly different. Terbinafine can be u sed for the treatment of microsporosis in cats in the dose of 30-40 mg/kg S ID. (C) 2001 Elsevier Science B.V. All rights reserved.