No, toxicity is not an issue with oral. And also, B12 does not have an upper limit set by FDA for toxicity either.
If your levels from the doctor are high (over 600) you won't need the 5mg for long. If 400 or below, it is best to take your 5mg for 3 months, and get a retest to see if it is working.
If you go over 1000, you can safely reduce to 1mg a day or use the 5mg every other or every 3 days instead to maintain. This is just a convenience factor in reality.
Some people it has been found by Dr. Snow in his paper back in 1999 just need more and do better on B12 even though fairly normal. And if you are not methylating properly you will need the methylB12 for life.
That's great and very promising that it is working for you so quickly.
Originally Posted by BetsyAnn
Just wanted to pop in and say a big THANKS for the reminder about B12. I don't know if it's helping, or a flare of sorts is subsiding, but who cares. My burns and tingles and pins and needles are much less, my strangling throat isn't so bad and I'm sooooo so thrilled about that.
I have the 5mg B12, I read at some spot to take it for a month and then switch to the 1mg. Or something like that. I (just now realize) haven't gotten my B12 results from the doc so I'll call again on that, but it isn't likely to ever get toxic is it? I have the (very tasty) Jarrow chew-able that I take first thing in the morning, if dose is ever an issue, could I just switch to qod or 3x/weekly?