Know the Ins and Outs of Giving mRNA COVID-19 Vaccines

Questions are cropping up about how to give the Pfizer-BioNTech or Moderna mRNA COVID-19 vaccines...as vaccination efforts expand.

Is it okay to mix and match COVID-19 vaccine doses? Only in RARE cases. There aren't data yet on using different products for each dose.

Review the vaccine record card or your state's immunization registry so patients get the same product for their first and second dose.

Is there "wiggle room" on timing of the second dose? A bit.

Pfizer-BioNTech's second dose is recommended 21 days after the first dose...Moderna's is recommended 28 days after the first dose.

If needed, it's okay to give the second dose up to 4 days early...such as if a patient returns ahead of schedule and might not come back.

And it's okay to schedule the second dose of either vaccine up to 42 days after the first dose if needed...based on current CDC guidance. But don't restart the series, even if the second dose is outside this window.

Are there tips to properly prepare doses and avoid errors? Yes.

For instance, remind staff that Pfizer-BioNTech's vaccine must be diluted and is 0.3 mL/dose...Moderna's is NOT diluted and is 0.5 mL/dose.

Use any extra full doses you can draw up...but don't "pool" excess vaccine from multiple vials.

Can COVID-19 vaccines be given along with other vaccines? Not yet.

In general, separate other vaccines (flu, etc) by at least 14 days from each COVID-19 vaccine dose. There are no data on co-administration, and this keeps the picture cleaner for evaluating adverse events.

Are there requirements for monitoring COVID-19 vaccine safety? Yes.

For example, report serious adverse events (anaphylaxis, etc) and administration errors to VAERS (Vaccine Adverse Event Reporting System).

Also give patients the required fact sheet...and highlight the info about "v-safe." It's CDC's voluntary smartphone tool that uses texts and surveys to check in about side effects after COVID-19 vaccination.

Access our chart, COVID-19 Vaccines, for storage and stability nuances, efficacy and safety details, and links to FDA fact sheets.

Also take a look at our Pharmacy Technicians University's PTU Elite: Immunizations training program. It helps techs meet requirements to give vaccinations...and be confident and prepared.

Key References

  • www.cdc.gov/vaccines/covid-19/info-by-product/clinical-considerations.html (1-26-21)
  • www.fda.gov/news-events/press-announcements/fda-statement-following-authorized-dosing-schedules-covid-19-vaccines (1-26-21)
  • www.immunize.org/askexperts/experts_cov.asp (1-26-21)
  • https://ismp.org/resources/learning-errors-new-covid-19-vaccines (1-26-21)
  • www.cdc.gov/coronavirus/2019-ncov/vaccines/safety.html (1-26-21)
Pharmacist's Letter. February 2021, No. 370202



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