can vitamin b12 injection cause diarrhea Understanding the Shot: Benefits, Risks, and Dosage Guide Vitamin B12 and ulcerative colitis:

On the other hand, it would seem that a lack of vitamin B12 can cause people to lose their appetite, resulting in a decrease in weight rather than an increase in weight

Injectable vitamin B12, which can treat significant deficiencies, may cause the following common side effects: More serious side effects of vitamin B12 injections can include: irregular heartbeat heart palpitations hives or a skin rash Vitamin B12 can cause very rare but serious allergic reactions, or anaphylaxis

My understanding ( not a scientist or doctor) Is liver stores run down slowly ovef years for many many reasons

store reconstituted material at 4C and use within ~30 days