A drug administration valve (100) comprises a valve housing (200) having a plurality of drug inlets (D1 to D4) for receiving drug fluids, such as cytostatic, one flushing inlet (F) for receiving a flushing fluid, and an outlet (O). A valve member (300) rotationally arranged in the housing has a passageway (320; 321) presenting a single inlet (322) and a single outlet (324).The valve member (300) presents a plurality of drug positions for guiding an associated drug fluid to the outlet (O), and one or more flushing positions for guiding a flushing fluid through the same passageway (320; 321) as the drug fluids in order to flush said passageway (320; 321) from any drug residuals. The valve member (300) is prevented from rotating from one drug position to another drug position without passing one of said flushing positions