• Welcome to Crohn's Forum, a support group for people with all forms of IBD. While this community is not a substitute for doctor's advice and we cannot treat or diagnose, we find being able to communicate with others who have IBD is invaluable as we navigate our struggles and celebrate our successes. We invite you to join us.

Oh, and a question about B12 shots

I recently started getting B12 shots. I get one every week for the first 4 weeks, and then once a month. Can anyone tell me how long it will be before I start feeling the effects (increased energy) of the B12? Thanks!


Punctuation Impaired
Hi Autumn Rose,
I never noticed a surge of energy after I get my shot. ...If I mess up my monthly schedule, it does seem to make a difference in how I feel. I always try to get it the week after my cycle starts so its the same time each month.
Hi Autum, I have had 4 weekly shots now and haven;t noticed any difference but I am also suffering the effects of tapering pred, so who knows!?
I take the B-12 in Nasal form. I've never noticed a real upswing but if I miss taking it I do notice a more run down feel till I start up again. Sorry, probably not what you wanted to hear.
I know I never suddenly felt more alert, it was more of a gradual process. I used to have a lot of trouble staying awake and alert and it went away after I started taking B-12. I don't recall how long it took me to feel the effects but for me it was noticeable. Before I'd fall asleep everywhere! In class, at bus stops or while I was cooking...
Last edited:
Thanks, everyone! I was kinda hoping to hear that I'd get an energy surge after the first month, but as long as I feel better in general, I'm good with that.

Wow, Wiles, glad to hear that you're no longer falling asleep while cooking! :p
I guess its different for everyone..for me I couldn't tell after the first because I had bad stomach flu..but I think it was about a week and I did feel so much more awake.


mum with a dogdy tum
i never had a energy boost after my vit b12 jabs. but if i am late in having them then i do feel run down.
My B12 shots started after my surgery in '97. If I miss taking the shot I am very worn out and wonder what my problem is. Then the big light bulb goes off and I realize I haven't had my shot. I have never once notice a surge in energy either, just felt more human is the best way to describe it for me.
Good luck! :bigsmurf: