QUESTION: I have a 50 yo female patient who had a rare and aggressive cancer (angiomatoid fibrohistiocytoma) in her left foot, plantar region, which she had removed and had a subsequent 8 weeks of radiation therapy in the fall of 2103. Since then she has dealt with a lot of neuropathic pain and the one thing that has helped her pain tremendously has been B12 injections. We have had her on these for about a year now, and a dosing of 1 cc B12 twice weekly seems to help the most. My question…would any of you be concerned about continuing B12 injections long-term for her? We were using MethylB12, but since the pharmacy changes, and expense, we have switched to hydroxycobalamin and the effect has been the same. We even did 3 injections of cyanocobalamin in a pinch while waiting for more stock and these were also effective. She is also on an oral methylB12 and folate. Any concern for long-term injections in your opinion?
ANSWER: In this type of situation with the response you mention the only thing I’d assure is that the other B-Vits and minerals required to metabolize the rest of the methyl cycle are going in. This is one of a few papers using a lot of B 12 and it was safe etc.
I do not worry about the long term use in cases like you describe, see excerpts and link to free papers:
“vitamin B12 levels and unsaturated vitamin B12 binding capacities were measured in 24 patients with multiple sclerosis (MS), 73 patients with other neurological disorders and 21 healthy subjects. There was no decrease in the vitamin B12 levels, however, a significant decrease in the unsaturated vitamin B12 binding capacities was observed in patients with MS when compared with other groups. A massive dose of methyl vitamin B12 (60 mg every day for 6 months) was administered to 6 patients with chronic progressive MS, a disease which usually had a morbid prognosis and widespread demyelination in the central nervous system. Although the motor disability did not improve clinically, the abnormalities in both the visual and brainstem auditory evoked potentials improved more frequently during the therapy than in the pre-treatment period. We therefore consider that a massive dose methyl vitamin B12 therapy maybe useful as an adjunct to immunosuppressive treatment for chronic progressive MS.” FULL TEXT
And: “Object: To study the effects of the intravenous administration of methylcobalamin, an analogue of vitamin B12, for uremic or uremic-diabetic polyneuropathy in patients who are receiving maintenance hemodialysis. An ultra-high dose of vitamin B12 has been reported to promote peripheral nerve regeneration in experimental neuropathy. Methods: Nine patients received a 500|ig methylcobalamin injection 3 times a week for 6 months. The effects were evaluated using neuropathic pain grading and a nerve conduction study.
Results: Serum concentrations of vitamin B12 were ultra-high during treatment due to the lack of urinary excretion. After 6 months of treatment, the patients’ pain or paresthesia had lessened, and the ulnar motor and median sensory nerve conduction velocities showed significant improvement. There were no side effects. Conclusion: Intravenous methycobalamin treatment is a safe and potentially beneficial therapy for neuropathy in chronic hemodialysis patients.” FULL TEXT