A syringe for dispensing a medicament comprises a cartridge, a plug and an activator member. The syringe comprises a main chamber containing a first liquid and an auxiliary chamber containing a second liquid. To activate the syringe and merging the first and second liquid to form the medicament the auxiliary chamber and the main chamber are connectable for fluid communication with each other. A movement of the activator member and/or the plug causes the second liquid to be transferred from the auxiliary chamber into the main chamber. The syringe helps facilitating the preparation of a medicament that has to be mixed from different liquids shortly prior to use.