I have a close friend for whom the B12 had no effect. However, his wife reported noticeable diminishment of the symptoms.
So, there is no guarantee except to check it out.
For the record, and for me an extremely important fact, the very common omeprazole prescribed and taken by many for indigestion, inhibits the action of B12 in the diet and as taken. By ceasing omeprazole, and beginning B12, the difference was unbelievable for me.
He is taking some in one of his multivitamins. I’ll have to check how much is in it. Unfortunately, I can’t do that for another week, as we are traveling. Visiting kids and grandkids for a week.
Thank you so much for your help.