Bioadhesive microspheres for ophthalmic administration of acyclovir.
J Pharm Pharmacol
; 49(8): 737-42, 1997 Aug.
Article
em En
| MEDLINE
| ID: mdl-9379347
ABSTRACT
The bioavailability of acyclovir to the ophthalmic epithelium is low and when the drug is administered in ophthalmic ointment it must be applied every four hours. An emulsification technique has been used to prepare acyclovir-loaded chitosan microspheres with the aim of promoting the prolonged release of drug and increasing its ocular bioavailability. The microparticulate drug-delivery systems obtained have been characterized for their morphology and physicochemical characteristics by in-vitro dissolution tests and in-vivo ocular administration to rabbits. The results show that the microspheres obtained are always quite small--the diameters of 90% of the particles are < or = 25 microns (i.e. d 90% never exceeds 25 microns) and physicochemical characterization shows that the drug is homogeneously dispersed in an amorphous state inside the microspheres. The in-vitro dissolution profile of acyclovir from chitosan microspheres is slower than that for the raw drug. Results from in-vivo ocular administration of acyclovir-loaded microspheres to the rabbit eye show prolonged high concentrations of acyclovir and increased AUC values. The microparticulate drug-carrier seems a promising means of topical administration of acyclovir to the eye.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Antivirais
/
Aciclovir
/
Quitina
/
Sistemas de Liberação de Medicamentos
Limite:
Animals
Idioma:
En
Revista:
J Pharm Pharmacol
Ano de publicação:
1997
Tipo de documento:
Article
País de afiliação:
Itália