There are two most common diseases that cause a clear nose that keeps running. Common cold, epidemic cold can cause runny, viral cold, so it is recommended to drink more water and can be properly supplemented with vitamin C. If there are many people around with the same symptoms, then accompanied by fever more serious symptoms, consider it to be epidemic cold, you can properly take antiviral drugs such as oseltamivir. If the runny nose is seasonal and regular, accompanied by sneezing and nasal itching, consider whether it is allergic rhinitis, and this disease needs anti-allergic treatment. Usually, you should strengthen physical exercise to enhance your body resistance.