A syringe equipped with: a barrel (110) having a drug solution inlet/outlet (112) provided on the tip thereof and an opening (115) provided on the back end and a plunger (120) comprising a gasket (122) which is provided on the tip end and is in sliding contact with the inner circumferential surface of the barrel (110) a flange (123) provided on the back end and a shaft (121) connecting the gasket (122) with the flange (123). The plunger (120) also comprises an auxiliary scale member (125) which is attached along the outside of the shaft (121) and on which a second scale (126) has been affixed. With regard to the second scale (126) a scale that aligns with the back end (114) of the barrel (110) is affixed so as to display the volume of drug solution contained inside the barrel (110) or the volume of drug solution to be administered that is contained inside the barrel (110).
