It has been a while since I've posted on this forum. Things for some time were getting better. I'm having some strange symptoms creep back up again, that I didn't have since around the time they found my B12 levels were low. So I have some hypothetical questions.

1) Would there ever be a situation in which a person couldn't live on B12 sublinguals alone? And they would NEED shots for life? From everything I read, the answer should be "no."

2) I haven't had my level check in a few months, but last time it was checked it was >2000. I wasn't taking shots, hadn't had one for months, and was on various sublinguals (Puritan's, Superior Source, Natural Factors, etc.). Could it be possible to have B12 deficiency symptoms with a level of >2000? (Again, haven't tested but I'm sure that's where my level is right now.)

The reason I ask these things is because a few months ago when I started to feel like I was getting B12 deficiency symptoms again (despite the reading of >2000... odd), I upped my B12 dosing from 5000 mcg/day sublingual to 2 X 5000 mcg/day sublingual (used Puritan's and Natural Factors). I also began giving myself weekly injections again, of methylcobalamin, 1mg/ week on Saturdays. Things started to improve by doing this. I stopped the injections about three weeks ago and have remained on 5000 mcg Puritan's everyday, sublingually. Within the last week I have noticed strange, vague back pains return that I didn't have until before both starting injections and the ramping up on B12 I did a few months ago.

Please don't tell me I need to restart shots! The only other thing I am thinking this is, is still my antidepressant withdrawal (yes, I am still going through that, it can last up to years I have read). It would make sense that this is just a resurgance of AD withdrawal symptoms and that B12 would help cool those down a bit, since it's a nervous system vitamin, and my nervous system needs a lot of repair.

Any advice is greatly appreciated, as always.