A filling aid is provided for filling a cylinder ampule (7) with a medical or pharmaceutical fluid. The filling aid in a common housing (4) includes a first receiver (24) which is configured for receiving the cylinder ampule (7) to be filled, and a second receiver (26) which is configured for receiving a receptacle (18) containing a medical or pharmaceutical substance. A first access opening (28) is formed on the first receiver (24) and is arranged such that the first access opening (28) lies opposite an opening of a cylinder ampule (7) when this cylinder ampule is inserted into the first receiver (24). A second access opening (30) is formed on the second receiver (26) and is arranged such that the second access opening (30) lies opposite an opening of a receptacle (18) when this receptacle (18) is inserted into the second receiver (26).
