摘要 |
The system having improved formulation properties, such as hardness and resistance to breakage, consists of a) an outer shell composed of a semipermeable material which is permeable to water and impermeable to the components of the core which contains the active ingredient, b) a core with a mixture which is sufficiently soluble in water to generate osmotic pressure and is composed of about 7.5 to about 15 % by weight of poly-N-vinylpyrrolidone, about 5 % by weight of a glidant or lubricant customary in the production of solid dosage forms, and about 80 to 92.5 % of a pharmaceutically acceptable metoprolol salt which is moderately soluble in water, and c) a passage through the shell a) for the transport of the components contained in the core into the surrounding aqueous body fluid. |