Injection compatibility: Suggested questions

Last updated: Monday, July 13, 2015

They may not apply to every situation you come across, but here are some questions you should be thinking about in practice.

The Medicine


  • Which drugs are currently being mixed? Which drugs are you planning to mix?
  • How will the drugs be mixed and what types of intravenous lines are in place?
  • What are the concentrations of the drugs, and what diluents are being used?
  • Will any of the drugs be stopped soon? Can any be stopped? (If not obvious.)
  • What other medication is the patient receiving – parenterally and otherwise?

The Patient


  • Are the number of intravenous access points limited? If so, why?
  • Can alternative routes of administration be considered? If not, why?
  • How is the patient being fed? (If there is an enteral feeding tube this may offer a potential alternative administration route; if TPN is being used this can create additional compatibility problems.)

Going Forward


  • What will happen if the drugs can’t be mixed?
  • Could additional IV access be provided?