Cold is also an acute infectious rhinitis, commonly known as "cold". It is caused by respiratory viruses, among which coronavirus and rhinovirus are the main pathogenic viruses. The virus is excreted from respiratory secretions and spread. When the body's resistance drops, such as colds, malnutrition, fatigue, excessive alcohol and tobacco, systemic diseases and chronic diseases of the nose itself affect the smooth respiratory tract, it is easy to induce infection. Secondary bacterial infection after cold attack. At the beginning of a cold, the nose feels dry and itchy, sneezing, general malaise or low fever, and then nasal congestion, decreased sense of smell, a lot of clear water running nose, congestion and edema of nasal mucosa, and a lot of clear water-like or purulent secretions gradually appear. There were no complications, and the course of disease was about 7- 10 days.

Because viruses live in human cells, no drug in the world can directly kill cold viruses. The effective way is to rely on the human immune system. Therefore, cold should be treated mainly, paying special attention to rest, drinking more water and eating lightly. This can give the immune system enough physical support.

A cold may cause bacterial infection, but don't take medicine casually. After the human immune system kills the virus, most infections will heal automatically. Blind drug treatment will enhance the drug resistance of bacteria and is not conducive to the normal function of human immune system. Because it is the process that the human immune system kills the virus, it is not very accurate to say that it is detoxification.