Abstract: Dispenser for dispensing a liquid, in particular a drug, such as for instance eye drops, which dispenser comprises two half portions which can be assembled by means of a snap lock to form a closed chamber adapted to surround a plastic bag containing the liquid, said bag having a constricted portion into which the reservoir of the bag extends, the constricted portion forming a neck with a dosage duct, through which the liquid, after breaking of the constricted portion, may be squeezed by compression of the plastic bag, one wall of the chamber of the dispenser being resilient to such an extent that the plastic bag can be compressed, and the dispenser comprising a shut off for sealing the dosage opening when no liquid is to be supplied.