@Roops
b12 cyanocobalamin injections is what is used for IBD type cases where the B12 levels are very low and it helps aid in the digestion/absorption of nutrients of the food going through the digestive tract. It is a red type liquid that you inject subq like insulin. I have never had an issue with the liquid staying in the needle it all was injected.
Methylcobalamin B12 - is different and it is what is used for nephropathy. It is usually in a pill/powder form. There are different ones out there. I used the Pure Encaspulations one and just added it into his pill capsules with all Jones' other meds. There are other popular ones here.
Rupert, or Roops, or Rupie does not have IBD. But he does have neuropathy. We had to ask the vet if that is what it was. The liquid B12 remained in the needle. My daughter just found a portion stayed inside the needle and never went into Roops because it was so low dose. 0.05. Now we know why. Intended for horses. Not for cats. I will be looking for Methylcobalamin B12. Thank you for your help.