has been refreshed! Take a tour.
  • Administering Vaccines
  • General Issues

Some manufacturers’ package inserts state that a vaccine should be used immediately after reconstitution. In the context of reconstitution and administration of vaccines, how does CDC define “immediately”?

There are various requirements for the use of vaccines after reconstitution. Some manufacturers’ package inserts require that the vaccine be used or discarded in varying time frames ranging from 24 hours after reconstitution to immediately after reconstitution. While the specific timeframes are simple to interpret, there can be some confusion as to what the requirement of “immediately” actually means.

CDC considers “immediately” to be the reasonable time it takes to prepare and transport the vaccine to the patient to be administered. This would include any limited documentation that may be related to this process. It is up to the judgment of a provider to determine if a vaccine has not been used in the appropriate time. Some manufacturers have indicated to providers that “immediately” can be up to 30 minutes. The definition of “immediately” varies from manufacturer to manufacturer. Some do not have the data to put forth a general time frame as to what “immediately” means. CDC recommends that the provider contact the manufacturer any time (s)he has any question about whether or not the vaccine has been used in the appropriate time frame.

Last reviewed: December 28, 2022

This page was updated on .