Abstract: Apparatus for administering intravenously a drug supplied initially in powdery form, in particular cytotoxic drugs, said apparatus comprising a sealed container for the drug, an infusion set supplying a drip feed of intravenous liquid to the patient and also being in communication with the interior of said sealed container, and a piston-cylinder pump assembly also in communication with the interior of said container in such a manner that appropriate actuation of the pump assembly can first of all draw intravenous liquid from the infusion set into the container to dissolve the drug into solution and thereafter can feed a controlled volume of said solution from the container to the patient. The apparatus thereby provides a closed circuit for the drug which can be administered without removing from the circuit any component containing or transporting the drug. The apparatus can readily be made opaque thereby avoiding photodegradation of photosensitive drugs being administered.