Carprofen Storage Times Extended

January 19, 2022


Recent information from the federal Office of Laboratory Animal Welfare (OLAW) requires us to rescind the extended “Beyond Use Date” for both diluted and undiluted Carprofen that was first announced in January. Accordingly, this agent must be used and discarded according to the manufacturer’s recommendations. We deeply apologize for any confusion this guideline retraction has caused.

The Guidelines on the Preparation, Storage and Expiration of Injectable Medications have been updated to reflect this important change in practice. Additional Questions? Please consult with your ULAM Faculty Veterinarian.

As part of our ongoing commitment to continually assess expiration/beyond use dates in therapeutic drugs, a recent internal U-M study has shown that the efficacy, potency, and sterility of Carprofen extends beyond the duration time(s) suggested by the manufacturer.

Accordingly, the Institutional Animal Care & Use Committee (IACUC), in close consultation with ULAM Faculty Veterinarians, has approved updates to the institution’s Guidelines on the Preparation, Storage and Expiration of Injectable Medications to extend the storage duration time(s) for the analgesic drug Carprofen.

Calendar icon with illustrated vials of carprofenSummary of Changes to Carprofen Storage Times

  • If refrigerated AND in a sterile vial → Up to 180 days
  • If at room temperature and/or in a conical tube → Up to 60 days

This change applies to both diluted and undiluted products. Please note that for all preparations, the extended expiration/beyond use date cannot go beyond the original expiration date on the stock vial.

For more information, review the Storing Injectable Medications section of the updated Guidelines to ensure appropriate storage and disposal of this analgesic.

Questions or Concerns?

  • If you have specific questions or concerns, or would like additional clarification on any aspect of the revised guidelines, please contact your ULAM Faculty Veterinarian.
  • If you don’t know your faculty veterinarian, send an inquiry to and your question will be routed appropriately.