Swollen lymph nodes in the armpit or axillary area has recently been recognized as a potential side effect of the COVID-19 mRNA vaccines. This is a temporary side effect that usually disappears a few weeks post vaccination. If you discover swollen lymph nodes after receiving the COVID-19 vaccine, don’t panic; this is just another way your immune system is letting you know it’s responding accordingly.
The Society of Breast Imaging officially recommends that if you need a breast imaging study, and it’s not an emergency, to get it done before your vaccination appointment. Once vaccinated, wait four to six weeks before getting a breast imaging study.