Consumers' confidence in the country's supervision on drugs was shattered after several sub-standard drugs killed dozens of people and the former head and senior officials of the administration were probed or jailed for graft.

Zhang Jixiang, a spokesperson of the administration, said there are more than 4,000 drug companies in China, which are required to register their products again to gain production approvals. The administration will filter the unqualified drugs, which may contain potential dangers, to secure the public's safety.

Zhang said the administration hasn't decided when the registration will end.

The administration is considering dispatching supervisors in drug plants from this year to ensure the quality of drugs.

Zheng Xiaoyu, a former director of the administration, was put under investigation on December 28 for allegedly taking bribes, an earlier report said.

Hao Heping, a former director of the Department of Medical Equipment and the former secretary of Zheng, was sentenced to 15 years in jail and confiscated of 200,000 yuan (US$25,674) for corruption and concealing guns in November.

Hao's department was in charge of issuing production licenses and quality control inspections.