英语语法分析

Take demulcent drug for a long time, can leucocyte decrease?

长期服用镇痛药，白细胞会减少吗？

And have demulcent effect good, with dosage little, hematic drug chroma is maintained constant wait for an advantage.

并且具有镇痛效果好，用药量少，血药浓度维持恒定等优点。

What thing is the demulcent stick that uses after the operation? Why to use with respect to indolence? What principle?

手术后使用的镇痛棒是什么东西?为什么用了就不痛了?什么原理?。