Why do some injections hurt Depending on the substance?

Messages
58
Likes
31
When I inject b12 it is painless mostly but when I inject b2 it hurts especially when I do it fast so I have to do it slowly and it is SUBQ or IM. IV is painless beside the initial hit into the vein especially if it is a core of multiple veins previously damaged etc.


I think the pain comes from in the skin were it activates P2X receptors expressed on nociceptive neurons and causes the pain. It hurts more on the shoulder than on the ass ...
 
Last edited:

Pearshaped

Senior Member
Messages
523
Likes
1,144
I dont have the english vocabulary to explain it Im afraid…
Some substances ie magnesium (and probably b2 ?) are „hypertonic“/ „hypertensive“ so they sting when injected.
Sarah Myhill explains it on her site where she talks about Mag injections.
B12 is not like that, and therefore totally easy to inject. It might help you to cool the skin before and afterwards and split the amount of B2 into two doses in two places on your body.
 

lenora

Senior Member
Messages
3,170
Likes
5,272
@Pearshaped, you did a good job.

Mg. is indeed painful, even if it's given by IV. That stuff burns for a long time. B-12 doesn't, and I can't help out with B2, but some injections can hurt far more than others. I hope it's at least helping you. Yours, Lenora.
 
Messages
58
Likes
31
Hurt less with time some facts are falsified. used to hurt so much injecting vitamin c in arm less in butt but now less. still hurts as much if a injected in a diff area .
Inhaleable and transdermal medicine are formulated same or similar as injectable ones so work to be injected. bacteria in nose is diff from the one in skin so nose medicine wont work.
 
Last edited:
Messages
58
Likes
31
inject upper high tissue more pain deeper less pain colour diff in ampoule than syringe (in diff lights/shades etc). pain when injected after multiple uses same area muscle loss etc needle point needle point used too much small bits of it come off microscopy and can be pushed into body skin when substances injected, but maybe too small compared to the bits off an ampoule to cause much damage if stuck in skin. More dosage more pain
 
Last edited:
Messages
13,142
Likes
30,142
Location
Second star to the right ...
When I was going thru chemo, I had to have 14-18 consecutive days out of every 21 of Neupogen/Epogen injections, and they hurt like hell. I was literally screaming with some of them, moaning loudly the rest of the time.

One of the nurses explained that proteins always hurt going in, and the larger the protein molecule, the greater the pain.

Mg injections probably burn going in because magnesium literally burns. It's an incendiary agent used for both illumination and as an anti-personnel system, usually in powdered form or small solid cakes ...

Vit C injections are painful because you're injecting some form of ascorbic acid. I would imagine that buffered C would hurt less. Possibly a lot less.

Vit B2 is a conjugate acid of riboflavin, so also acidic, which would burn more than a moderate base. It's only very slightly soluble in an aqueous solution, but dissolves readily in strongly acidic liquids.

EDIT ... for clarity. Of which I have little to spare ..... Also, 3 or 4 typos ...
 
Last edited: