PURPOSE: To obtain a sustained release oxybutynin hydrochloride pharmaceutical preparation, orally administrable and having prolonged action properties.
CONSTITUTION: The sustained release oxybutynin hydrochloride pharmaceutical preparation is characterized by blending a gel-forming substance such as hydroxypropyl methyl cellulose and ≥12C higher alcohols in a pharmaceutical composition containing the oxybutynin hydrochloride and an acidic substance. Since this sustained release oxybutynin hydrochloride pharmaceutical preparation is capable of controlling the release of the oxybutynin hydrochloride, reducing the maximum level in blood plasma as compared with that of a conventional pharmaceutical preparation and providing a constant level in blood for a long period, it can be formed into a daily once or twice administrable type pharmaceutical preparation.
NAKAMURA TAKANORI
MAEDA YOSHIO
IGARASHI TAKAKO
YASAKA KATSUYOSHI
