Editing Intravenous therapy (section)

===Secondary===
Any additional medication to be administered intravenously at the same time as an infusion may be connected to the primary tubing; this is termed a secondary IV, or IV piggyback.<ref name=CCM2010 /> This prevents the need for multiple IV access lines on the same person. When administering a secondary IV medication, the primary bag is held lower than the secondary bag so that the secondary medication can flow into the primary tubing, rather than fluid from the primary bag flowing into the secondary tubing. The fluid from the primary bag is needed to help flush any remaining medication from the secondary IV from the tubing.<ref name=CCM2010 /> If a bolus or secondary infusion is intended for administration in the same line as a primary infusion, the molecular compatibility of the solutions must be considered.<ref name=CCM2010 /> Secondary compatibility is generally referred to as "y-site compatibility", named after the shape of the tubing which has a port for bolus administration.<ref name=CCM2010>{{cite journal |last1=Kanji |first1=Salmaan |last2=Lam |first2=Jason |last3=Johanson |first3=Christel |last4=Singh |first4=Avinder |last5=Goddard |first5=Rob |last6=Fairbairn |first6=Jennifer |last7=Lloyd |first7=Tammy |last8=Monsour |first8=Danny |last9=Kakal |first9=Juzer |title=Systematic review of physical and chemical compatibility of commonly used medications administered by continuous infusion in intensive care units |journal=Critical Care Medicine |date=September 2010 |volume=38 |issue=9 |pages=1890–1898 |doi=10.1097/CCM.0b013e3181e8adcc|pmid=20562698 |s2cid=205539703 }}</ref> Incompatibility of two fluids or medications can arise due to issues of molecular stability, changes in solubility, or degradation of one of the medications.<ref name="CCM2010" />