Blog #23: Multi-dose Vial Expiration Date vs BUD-Beyond Use Date

Today most vaccines used in travel health come in single use vials or pre-filled syringes. A few vaccines can still be ordered in multi-dose vials such as injectable typhoid and inactivated IPOL polio. Nurses will sometimes ask, “When must you discard a multi-dose vial?” Other nurses have asked “What exactly is a BUD and how does that differ from a vaccine expiration date?”

This ATHNA Blog will answer both questions using information from CDC for US practice and PHAC for Canadian practice.

Discarding A Multi-Dose Vial

A multi-dose vial (MDV) contains more than one dose of vaccine. Because MDVs typically contain a preservative to help prevent the growth of microorganisms, they can be entered or punctured more than once. Only the number of doses indicated in the manufacturer’s package insert should be withdrawn from the vial. After the maximum number of doses has been withdrawn, the vial should be discarded, even if there is residual and the expiration date has not been reached. Never use partial doses from two or more vials to obtain a dose of vaccine.

Per CDC: A multi-dose vial of vaccine that has been stored and handled properly and is normal in appearance can be used through the expiration date printed on the vial. Never use expired vaccine or diluent and immediately remove them from your storage unit. If the date on the label has a specific month, day, and year, the vaccine can be used through the end of that day. If the expiration date on the label is only printed as a month and year, the vaccine can be used through the last day of that month.

Example: Injectable Typhoid

This vaccine can be ordered as an MDV with 20 doses. As long as the vaccine has been properly handled and not contaminated, the nurse can withdraw 20 doses of vaccine until the expiration date. Even if there is residual vaccine fluid in the vial the nurse cannot withdraw more than 20 doses and must discard the vial after the expiration date printed on the label.

The BUD- Beyond Use Date

Be aware of instances when vaccines expire before the expiration date on the label. Sometimes vaccines must be discarded before the expiration date—by an earlier date known as the “beyond use date” (BUD).

  • Some manufacturers replace the expiration date with a BUD for select vaccines. If a vaccine has a BUD it will be printed in the package insert.
  • The BUD replaces the expiration date on an opened vaccine vial- single or multiple dose.
  • The BUD is calculated based on the date and time the vial is first entered /punctured with a needle.
  • Manufacturers assign BUDs for various reasons: Some vaccines should be used within a certain time frame after the first time a needle is inserted , after the vaccine is reconstituted (e.g., vaccines requiring reconstitution), or if the manufacturer deems it is necessary to shorten the expiration date.
  • Manufacturer-shortened beyond use dates may apply when a vaccine is exposed to inappropriate storage conditions. The manufacturer might determine that the vaccine can still be used, but will expire on an earlier date than the date on the label.
  • When opening a new vial of vaccine, check the package insert to determine if the vaccine has a BUD, and if so for the correct time frame (e.g., days, hours) the vaccine can be stored once the vial has been entered or has been reconstituted.
  • Calculate the BUD using the time interval found in the vaccine’s package insert. Label the vaccine with the correct beyond use date/time and your initials.
  • If a vaccine has a BUD then discard that opened vial according to the BUD, not the expiration date.

Example: MMR

If a particular vaccine has a BUD, such as MMR, it is spelled out in the manufacturer’s package insert. Every vial of MMR will have its printed expiration date on the label, but the manufacturer instructions printed in the package inset indicate that once a needle enters an MMR vial, it must be discarded in 8 hours. The BUD in this case is 8 hours from the time when the vaccine was opened and reconstituted even if the unopened MMR vial has an expiration date that could be months or years hence.


  • Be mindful that some institutions may have their own vial discard guidelines. Check to confirm your clinical site’s standard operating procedure.
  • Also keep in mind that there are national standards for vaccine storage and handling. In the United States that standard is the 2016 CDC Vaccine Storage and Handling Toolkit
  • In Canada the standard is the same and can be found in the PHAC Immunization Guide 2017.
  • International standards, such as WHO, may differ from these national standards and are not applicable.
  • Be wary of outdated guidelines. On the Internet you can easily find guidelines from OSHA, the US General Pharmacopeia and others that predate the current standard. Do not rely on old guidelines; always check to be sure you are using the most up-to-date standard. Check publication dates carefully.


Two excellent US resources cited for this and other vaccine storage and handling issues:

Immunization Action Coalition Storage and Handling @

CDC Pink Book Storage and Handling @

For vaccine package inserts:

IAC publishes vaccine package inserts @

The Canadian resource for storage and handling issues:

National Vaccine Storage and Handling Guidelines 2017