| 摘要 |
The microspheres are composed of a core containing the active principle and a microporous membrane which is insoluble in aqueous media, the membrane consisting of a film-forming polymer, a plasticiser and a filler. The membrane has a thickness such that, in vitro, the diltiazem is released at a substantially constant rate for at least 6 hours, after a latency time of less than 1 hour. The active principle may be mixed intimately with the core, or coated in a layer of polyvinylpyrrolidone surrounding a carrier particle. The sustained-release microspheres are formed by application to the core of a dispersion of the constituents of the membrane in a solvent, and evaporation of the solvent. The pharmaceutical compositions consist of hard gelatine capsules containing the microspheres. They are administered, according to the dose, once to twice a day orally for the treatment of angina or hypertension. |
