A five-year-old girl has been diagnosed as having an allergy to her own tears which causes her face to end up red and swollen each time she cries.

The girl’s mother, identified only as Ms Deng, told local media in the city of Hanzhong in the Shaanxi Province, China, that she knew that her daughter had sensitive skin.

But she was shocked when she learned the child had developed a new kind of allergy which causes her tears to leave red marks and make her face swollen as they flow.

Her mother told local media that every time her daughter cried, she was left almost disfigured and it was disturbing for all of them.

Ms Deng told local media: “After she started using medicines, her condition significantly improved.

“Every time my daughter wants to cry, she has to receive her medicine.”

According to Cleveland Clinic, allergies are caused when the body reacts to foreign, normally harmless proteins, also called allergens.

When the immune system overreacts to the presence of a particular protein in the body, it is classified as an allergic reaction.

The symptoms can vary from mild to life-threatening.

They are not contagious, however, and cannot cause fever.