I take Xyrem - a sleep medication - is that allowed in the country

I've heard from other people that take this medication that they have had issues bringing their prescription Xyrem into China. I'm going to Hong Kong and then Shen Zen for just a few days on business.

Will i be permitted to bring just the amount needed for me for the 5 days in the country, will I be allowed to bring it? It is a very regulated drug in the USA. i've had no issues taking it into Canada or Europe but I know CHina has much stricter regulations. Is it a banned item with no acceptance at all or do i need special paperwork?

Thank you