By Yi Whan-woo

North Koreans have been refusing to buy Chinese medicines in the wake of a vaccine scandal and safety concerns in China, according to sources familiar with the matter.

China experienced one of its worst public health crises in July when vaccine maker Changsheng Biotechnology was found to have fabricated production and inspection records of its freeze-dried human rabies vaccines.

"Many North Korean patients and their families who used to buy Chinese medicine now seriously question whether they should keep using it or not," a source told Radio Free Asia.

"Those who have heard that China often has trouble with fake medicines now distrust the Chinese medicines available in local markets."

Sources in Dandong, China, said the vaccine scandal was causing increased demand for South Korean medicine among North Koreans there.

"North Koreans are surprised at how effective the South Korean medicines are, and they just sweep them up from the shelves as soon as they are stocked," the source said. "North Korea can't produce good-quality medicines, so most North Korean residents have had to rely on Chinese medicines.

"But because these are now often involved in product safety scandals, North Koreans are showing a greater level of trust in medicines made in South Korea."

North Korea relied on Chinese medicine because of U.N. Security Council sanctions made it difficult to obtain medicines including painkillers and fever-reducing drugs formerly brought in by the Red Cross and other international organizations.