You have a headache and you sneeze and cough. Your nose is all stuffed up, and it keeps running, so you have to blow it every few minutes. You know by these symptoms that you have a cold, and you feel completely miserable. Everyone suffers from the common cold at some time or other. It isn’t a serious illness, but nothing can cure it. Medicine can relieve the symptoms. That is, it can make you cough less, make your head less intense, and stop your nose running for a while. So far there has been no cure for the common cold and no medicine to prevent it. Although there is no cure or preventive medicine for colds, people have all kinds of ideas about how to prevent and treat colds. Some people think that if you eat a lot of onions, you won’t get cold. Others say that you should avoid getting wet, or you will catch a cold.