Glehnia littoralis (in the monotypic genus Glehnia) is a species of plant in the "carrot family", Apiaceae, known by several common names including beach silvertop and American silvertop in English, and bei sha shen (Chinese: -) and shan hu cai (Chinese: -) in Chinese. The genus was named after Russian botanist Peter von Glehn.
It is native to eastern Asia, particularly eastern China, Japan, and far-eastern Russia, and western North America from Alaska to northern California.
It is a long-taprooted plant forming a basal patch of leaves, with each leaf made up of several rounded, lobular segments. It reaches a maximum height exceeding half a meter and its erect stem is topped with an umbel of carrotlike white flowers.
The plant is perhaps best known as a Chinese herbal remedy for cough. It contents naphthisoxazole A: