鼻涕多到鼻腔都滿溢,所以倒流去喉嚨.低濃度緩衝液鹽水能稀釋鼻粘液，

使鼻涕變得容易擤出來.

http://www.xinhuanet.com/local/2021-01/05/c_1126945758.htm

https://www.haodf.com/neirong/wenzhang/9029983007.html