Hi Megan, i think its been explained perfectly so i just wanted to add that sometimes increase in symptoms also can be the person becoming tolerant to the whatever drugs, this happened to me, so i backed off the drug for about a week then went back up to initial dose, then it worked again properly, so just to confuse us more it can be a fine line in trying to distinquish between repairing & drug tolerance.

Just curious about your mum's ordeal with low B12, did she have nerve damage ?
or showing other symptoms, i am glad the Hydroxocobalamin shots worked for her anyway

Brian