Zhejiang Haisen Pharmaceutical Co., Ltd. and its subsidiaries research, develop, produce, and sell pharmaceutical intermediates, active pharmaceutical ingredients (APIs), and preparations in China and internationally. Its APIs are used in antilipemic agents, antipyretic analgesics, antidepressants, analgesics, antibacterial agents, histamine drugs, anticonvulsants, and products for anti-gastric ulcers and digestive and cardiovascular applications. The company also supplies chemical products used as paroxetine HCl and amikacin sulphate intermediates and food additives, and sells escitalopram oxalate tablets for depression and panic disorders under the Tezi brand. It is additionally involved in goods import and export, trading, and medical research and experimental development. Incorporated in 1998, the company is headquartered in Dongyang, China.