1.
poisonous drug; toxic medicine; poison (pharmaceutical)
A pharmaceutical substance classified as highly toxic, requiring strict controls on its handling, storage, and dispensing.
Containers of poisonous drugs are marked with the character 毒 in white on black.
A pharmaceutical and legal term. In Japan's drug classification system, 毒薬 is the most dangerous category — medicines that can be lethal in small doses. They must be stored in locked cabinets and must carry a label with the character 毒 in white on a black ground inside a white border (黒地に白枠・白字). 劇薬 labels are the reverse scheme in red: red characters and a red border on white. Below 毒薬 is 劇薬 (powerful drug), which is dangerous but less lethal.