Medical Toxicology Reporting of Adverse COVID-19 Vaccine Events

by Brenna Farmer, MD and Andrew Stolbach, MD

The US has been vaccinating well over one million people daily against COVID-19 even prior to the authorization of the newest vaccine. These vaccines have proven remarkably safe. The most common adverse reactions are local reactions and general soreness. The most severe adverse effect- anaphylaxis- is occurring in fewer than one in a million shots. We are still learning more about other adverse events, like immune thrombocytopenia, that occur in the days following vaccination.  

Medical toxicologists can play an important role in the recognition and reporting of adverse vaccine events. ACMT has set up the FDA ACMT COVID-19 ToxIC (FACT) Pharmacovigilance Project Sub-registry at 15 sites across the country. Medical Toxicologists at each of these sites are reporting ADRs to COVID Therapeutics (including vaccines) directly to the FDA utilizing a newly established reporting system established by ACMT under a contract with the FDA. 

Moreover, for those ACMT members not associated with one of these 15 sites, here are some other ways to report adverse vaccine events.

How to Report Adverse Vaccine Events:  

Report severe effects, like anaphylaxis, thrombocytopenia, or other suspected events to the Vaccine Adverse Events Reporting System (VAERS). Reports are easy to complete online at Demographic, medical history, and vaccine information will be needed to complete the report. 

Tryptase Concentration and COVID-19 Vaccine Reactions  

Tryptase, a mast cell product, is elevated in blood after anaphylaxis. Consider obtaining a tryptase blood level (usually ELISA) when caring for patients suspected of COVID-19 vaccine allergic reaction. Ideally, the test should be checked within an 1-3 hours of the event.  Tryptase levels can help differentiate anaphylaxis from other reactions and can be very helpful during follow-up visits. 

How Patients Can Track and Report Vaccine Reactions: 

Encourage patients to use the V-safe smartphone tool to report any and all vaccine reactions and side effects after COVID-19 vaccine. It can be found at These reports go to CDC, who will contact patients if they have further questions or concerns. Patients will be reminded to report any side effects over a period of time to help with monitoring and determining the common and rare side effects.