Desenvolvimento de comprimidos de fipronil para c?es: farmacocin?tica e efic?cia ectoparasiticida

• Autor(a) principal: Santos, Gabriela Carmelinda Martins dos
• Data de Publicação: 2018
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFRRJ
• Texto Completo: https://tede.ufrrj.br/jspui/handle/jspui/4763
• topic: Fipronil; Farmacocin?tica; Efic?cia ectoparasiticida; Pharmacokinetics; Ectoparasiticide efficacy; Qu?mica

Fipronil (FIP) is an insecticide belonging to the class of phenylpirazoles. It is widely used as an insecticide in agriculture and in veterinary medicine. Its mechanism of action is involved with blocking the signal transmission due to the ?-aminobutyric receptor antagonism (GABA) present in acari and insects. Increased human-pet interaction makes concern for the prevention and treatment of flea and tick infestations. The products commercially available for ectoparasites treatment in dogs and cats are mostly in the topical form, however they are associated with damage to the animal, owner and to the environment, due to uncontrolled exposure to the drug, leading to requirement of new product development. Pharmaceutical forms for oral administration of drugs are most common used for the convenience they provide, constituting a non-invasive route of administration and having a low cost. The objective of the study was the pharmacotechnical design and physical-chemical quality control of immediate release tablets of fipronil, as well as to determine its pharmacokinetics and the ectoparasiticide efficacy in dogs. The results showed that it was possible to produce FIP tablets according the criteria established in the Brazilian pharmacopoeia. In vitro release studies have shown that the best diluent to be used in tablet development is lactose due to the appropriate release profile for immediate release tablets. FIP administered orally at the dose of 2 mg/kg reached the systemic circulation (Cmax = 2.17 ? 0.84 ?g/mL) and was fast absorbed (tmax = 2.67 ? 1.37 h) and metabolized, once its SULF metabolite presented Cmax = 1.32 ? 0.55 ?g/mL in a tmax = 3.5 h. Both elimination, FIP and SULF occurred slowly (t1/2 = 385.93 ? 405.31 h) and (t? = 385.93 ? 36.26 h) respectively, maintaining quantifiable plasma levels in the blood for up to 28 days after treatment. The in vivo ectoparasiticide efficacy tests proved that FIP administered orally at the dose of 2 mg/kg had a efficacy of 80% against C. felis felis for 15 days after treatment but it did not show any efficacy against R. sanguineus.