Why does the penicillin skin test solution need to be prepared at the time of use, and what is the purpose of its preparation?

Gastrodia Elata has a sweet and mild nature, and it is used for calming wind and stopping spasms, soothing the liver Yang, and removing wind to unblock meridians. It is primarily used to treat symptoms such as internal liver wind, dizziness, and headache.

How should you medicate a child with a cold and runny nose?