The use of a specific device is claimed for implantation or insertion of a solid or semi-solid formulation (F), containing an active ingredient (A), into an organism at a precise receptor site. The device includes a component which is inserted into the body of the patient, can store (F) and can position (F) the precise site where it is required. The injection or insertion of (F) can be controlled externally. The device is withdrawn after (A) has been so placed. Formulations for use in the device are also claimed, specifically containing at least 50% of (A) mixed with a polylactide-glycolide copolymer (PGLA).
