Since the common cold and flu in the community recently are mostly caused by virus, Dr will not recommend you to take Antibiotic. And the other stuff like cough, runny nose medicine are 治標不治本. This is why the Dr ask you 盡量不要食藥. Make sure you have sufficient rest and drink plenty of water. And avoid other sick people. In fact, there are some medicine safe for pregnant women but I agree with your Dr not to take unless it is really really necessary.