In rarer cases, vitamin B12 can cause more serious side effects such as an irregular heartbeat or heart palpitations, hives, and anaphylaxis
(PubMed) Stabler SP, Lindenbaum J, Allen RH
Verified Answer In addition to Metronidazole capsules I have ordered, vet recommended VitB-12 shots
Kirkland, Niacin Status, NAD Distribution and ADP-Ribose Metabolism, Curr
Adverse drug reactions observed in the mecobalamin 50 mg group were constipation, injection site pain, fever, electrocardiogram QT prolongation, and rash, occurring in 1.5% (1/65 cases) each
Vitamin B12 is a water-soluble vitamin that plays a vital role in the production of red blood cells, neurological function, and DNA synthesis