Busan District Prosecutors' Office said Sunday it arrested and charged a pharmacist on suspicion of making diet food with obesity medicines and selling it online.
Korea does not allow obesity medicines to be used in food manufacturing.
The 66-year-old suspect, only identified by his surname Park, allegedly mixed powdered persimmon leaves with sibutramine (reductil).
He sold 2,362 boxes of the illegal product via cosmetic shops and online stores, according to prosecutors.
Sibutramine is known to have appetite-repressing effects and is sold under a variety of brands.
However, safety concerns were raised in the US over the relatively high number cardiovascular problems observed in people taking sibutramine.