Thank you so much for your response; the pain has gotten so bad recently. It's so frustrating since I thought I was most "cured" (also been dealing w/other health issues).

I'm really becoming convinced that the increased pain is related to the lactoferrin form of iron I started at right around the same time (they have checked ferritin multiple times, that's what clued them in that I was anemic: levels of 10-20).

Then again, the same issues that cause the low iron (gastroparesis, chronic gastritis, low acid due to nexium/PPI) could also cause B12 issues, I think. I'll have to consider that.

I've stopped the iron supplements and am focusing on trying to get them up naturally, and trying again to taper down the Nexium (I tapered once and it made me so sick I was vomiting). This time more slowly.

I went 10 years without this kind of major pain, and it started within a week of me starting to supplement iron (using lactoferrin). It just seems to coincidental to not be related. Of course, I also started Vit D supplements about a month before that.