Rick what you have done is similar to how doctors treat b12 deficiency, with what they call loading doses. Lots initally to get you going then back down. If a person has a long standing deficiency this doesn't work so well. My guess is that as PwP we are well on the road to understanding how to manage medications, and given half a chance I would self medicate with B12, but am needle-phobic, and don't have the right cells to absorb it. Sub0linguals are maybe a way forward.

Always interested in anyone dealing with this and PD, its is a double whammy.