According to the Centers of Disease Control (CDC), there are no mandatory immunization shots to be taken to enter China.
China Focus Travel recommends that you have hepatitis A and B vaccines.
It is always a good idea to update your routine shots such as MMR and DPT vaccine.
It is best to keep your prescription medication in original bottles.
If using a pillbox, you must bring written documentation stating what type of drugs you will bring and what they are for.
As for vitamins, you may peel off the label on the bottle as your documentation.