Country: South Africa
Language: English
Source: South African Health Products Regulatory Authority (SAHPRA)
Dr-reddy
DERMAX 250 (tablets) SCHEDULING STATUS S4 PROPRIETARY NAME (and dosage form): DERMAX 250 (tablets) COMPOSITION DERMAX 250 : Each tablet contains 250 mg terbinafine as terbinafine hydrochloride PHARMACOLOGICAL CLASSIFICATION A20.2.2 Antimicrobial (Chemotherapeutic) agents. Fungicides. PHARMACOLOGICAL ACTION Pharmacodynamics Terbinafine is an allylamine which has a broad spectrum of antifungal activity. At low concentrations terbinafine is fungicidal against dermatophytes, moulds and certain fungi. The activity is fungicidal or fungistatic depending on the species. Terbinafine interferes specifically with fungal sterol biosynthesis at an early stage. This leads to a deficiency in ergosterol and to an intracellular accumulation of squalene, resulting in fungal cell death. Terbinafine acts by inhibition of squalene epoxidase in the fungal cell membrane. The enzyme squalene epoxidase is not linked to the cytochrome P-450 system. When given orally, the medicine concentrates in skin at levels associated with fungicidal activity. Pharmacodynamics: A single oral dose of 250 mg of terbinafine results in mean peak plasma concentrations of 0,87 micrograms/mL within 2 hours after administration. The absorption half-life is 0,6 hours and the distribution half-life is 4,6 hours. Terbinafine binds strongly to plasma proteins. It rapidly difuses through the dermis and concentrates in the lipophyllic stratum corneum. Terbinafine is also secreted in sebum, thus achieving high concentrations in hair follicles, hair and sebum rich skins. There is also evidence that terbinafine is distributed into the nail plate within the first few weeks of commencing therapy. Biotransformation results in metabolites with no antifungal activity, which are excreted predominantly in the urine. The elimination half-life is 17 hour Read the complete document