A drug supply unit that supplies a solid drug, and includes a drug container that stores a drug, and a driven shaft that is rotatably provided to the drug container, and the driven shaft rotates. A drug supply body that supplies a drug from the drug container by being driven, a rotation drive source, and a drive shaft portion that is coaxially connected to the driven shaft portion and is driven to rotate by the rotation drive source. And a support body that detachably supports the medicine supply body, wherein the driven shaft portion is a driven shaft portion main body and a driven portion that is movable in the axial direction with respect to the driven shaft portion main body. The drive shaft portion includes a drive shaft main body, a drive engagement member fixed to the drive shaft main body and engaged with the driven engagement member, and the driven shaft portion. The drive engagement member is biased in an approaching direction approaching the drive engagement member, and the medicine In a mounted state in which the feeder is mounted on the support, the driven engagement member is allowed to rotate when the driven engagement member is engaged with the drive engagement member. The drug supply unit further includes a rotation preventing portion that prevents rotation of the driven engagement member when the driven engagement member and the drive engagement member are in contact with each other without being engaged. .固形の薬剤を供給する薬剤供給ユニットであって、薬剤を収容する薬剤収容部、及び、当該薬剤収容部に対して回転可能に設けられる被駆動軸部を有し、前記被駆動軸部が回転駆動されることで前記薬剤収容部から薬剤を供給する薬剤供給体と、回転駆動源、及び、前記被駆動軸部が同軸に接続されており前記回転駆動源によって回転駆動される駆動軸部を有し、前記薬剤供給体を着脱可能に支持する支持体とを備え、前記被駆動軸部は、被駆動軸部本体と、当該被駆動軸部本体に対して軸方向に移動可能な被駆動係合部材とを有し、前記駆動軸部は、駆動軸部本体と、当該駆動軸部本体に固定され、前記被駆動係合部材に係合する駆動係合部材とを有し、前記被駆動係合部材は、前記駆動係合部材に接近する接近方向に付勢され、前記薬剤供給体が支持体に対して装着される装着状態において、前記被駆動係合部材と前記駆動係合部材とが係合する係合状態のときは、前記被駆動係合部材の回転を許容し、前記被駆動係合部材と前記駆動係合部材とが係合せずに当接する当接状態のときは、前記被駆動係合部材の回転を阻止する回転阻止部をさらに備える薬剤供給ユニットである。
