Methods:The dextromethorphan oral sustained-release suspensions were prepared using ion exchange resin as a carrier,and followed by coating with ethylcellulose using the Wurster fluid bed process.

• 方法:采用离子交换树脂为载体制备含药树脂微粒,用流化床进行包衣,并通过处方优化制备右美沙芬树脂口服缓释混悬液。