That’s not really true, we give lots of drugs IM because the muscle is highly vascular so it generally shoots out all over the body really quickly. Ie want to take down a patient with Ice (crystal meth) induced psychosis? IM. Also, it’s hard to miss most of the time.
If you want something to sit around for a long time, you go for less vascular areas. (Ie insulin for diabetics, subcut abdominal fat)
IM is preferred because of the vascularity which helps in the immune response (ie quick immune response, antigen distributed around the body) as well as any immune reaction confined to the muscle rather than, say the skin.
(0) is a quick and dirty on mechanisms of administration.
To your earlier point about ‘into’ a vein, I’d never heard of Dr Campbell before you mentioned him, he seems to have great credentials, but I can’t easily explain why an accidental IV administration of an IM vaccine would cause CVST, my gut is that it’s a bit of a hand wave but who knows.
Time periods seem off (5-14hrs) in mouse models compared to what’s being seen here though, which seems more like an immune reaction rather than a response to the antigen/delivery system
If you want something to sit around for a long time, you go for less vascular areas. (Ie insulin for diabetics, subcut abdominal fat)
IM is preferred because of the vascularity which helps in the immune response (ie quick immune response, antigen distributed around the body) as well as any immune reaction confined to the muscle rather than, say the skin. (0) is a quick and dirty on mechanisms of administration.
To your earlier point about ‘into’ a vein, I’d never heard of Dr Campbell before you mentioned him, he seems to have great credentials, but I can’t easily explain why an accidental IV administration of an IM vaccine would cause CVST, my gut is that it’s a bit of a hand wave but who knows.
(0) https://www.forbes.com/sites/quora/2017/11/07/why-arent-vacc...