You should get B12 shots weekly to monthly for maintenance and IV infusions monthly to quarterly for broader wellness support, though frequency depends on deficiency severity, health goals, and your providers recommendation
Clots in the arms and legs, low potassium levels in the blood, allergic reactions (also typically linked to a preexisting allergy that you suffer from), or congestive heart failure, are some of the most serious side effects which can occur
Other Uses Compounded methylcobalamin injections and other forms of vitamin B12 injections like hydroxocobalamin and cyanocobalamin may also be prescribed for those with pernicious anemia, diabetes, neuropathy, heart disease, circadian rhythm sleep disorders, memory loss, depression, fatigue, AIDS, inflammatory bowel disease (IBD), Lyme disease, osteoporosis, tendonitis, psychiatric disorders, Alzheimers disease, liver and kidney disease, and asthma
Second, some absorption of intact peptides does occur through the intestinal barrier
