Subcutaneous (Fat) vs Intramuscular Injections

[lownskater52]

Hello,

Is there any difference in efficacy between getting a b12 shot in muscle vs in fat? I got my bi-daily methly b12 shot today and I had a new nurse and she suggested a shot in the hip/glute rather than the arm. I have always had it in the arm but went along with the hip suggestion. Now my leg muscles are pretty wasted including my hip/glute which leaves that area mostly fat. Not sure she got into the muscle. Does it make a real difference? I've read that it doesnt.

With love.

[pvanderaa]

Very little difference between subcutaneous and inter muscular B12 injections. 25 mm needle for IM and 12 mm for subc.

I self inject IM in the buttocks or hip with a 25 mm needle and it does go into the muscle.

[GastritisB12]

I tried my first self-injection last month into sub cutaneous fat and it seemed to work. I still got a rash of small spots on my face for a few days after which is what I got with NHS-administered intramuscualr injections too so I guess it worked?

[fbirder]

If the B12 gets into your body then it has to get into the bloodstream before it can get out again. That means that any type of injection will deliver 100% of the dose into the blood. The only difference would be the speed at which it gets into the blood.

Nobody knows which would be fastest, IM or SC. Many assume IM, only because it is more highly perfused with blood. But some drugs (not just fat soluble ones) move into the blood more rapidly from SC than IM. Until somebody does the test there's no real way of knowing.

[pvanderaa in reply to fbirder]

I’m of the opinion that I want the B12 to get into the blood as “slow as possible”. If I wanted to get it into the blood stream as fast as possible, I could inject intravenous (IV).

However, then the kidneys would clean it out and it would all go straight down the drain.

I inject IM because it seems slower and lasts longer. I avoid sleeping on the most recent injection site to keep from pushing the B12 out of the muscle.

[fbirder in reply to pvanderaa]

Yup. In theory a slower release from the injection site is ideal.

The problem is that nobody knows which is the slower release, IM or SC.

[Miss-guineapig]

No right or wrong, both work, so nothing to worry about x