Left or right arm: Choosing where to get Covid vaccine matters, study suggests

usatoday.com

5 pointsbookofjoe4 comments

>People may respond better to sequential shots in the same arm because the vaccines are targeting the same lymph nodes

I was told by everyone I asked that the medicine stays local to the muscle in your arm, that they aren’t intended to enter the bloodstream or target other organs. Is that wrong?

> Intramuscular injection (IM) is installing medications into the depth of specifically selected muscles. The bulky muscles have good vascularity, and therefore the injected drug quickly reaches the systemic circulation and thereafter into the specific region of action, bypassing the first-pass metabolism.

https://www.ncbi.nlm.nih.gov/books/NBK556121

Perhaps contrary to what you’re saying, many published studies say that mRNA injections stay in the muscle and local lymph nodes, not reaching systemic circulation in a meaningful way. See “Where does the vaccine go?” here which cites two studies: https://www.nebraskamed.com/COVID/where-mrna-vaccines-and-sp...

I guess I didn’t realize getting to nearby lymph nodes was part of “local to the muscle”

Why are we still talking about this ?

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