best place to inject b12 shot Vitamin Injection Site: Administering B12 Shots Safe B12 Injection Guide at

If your deficiency is mostly from diet, recovery is often faster once intake is corrected

Bacterial overgrowth of the small intestine may lead to low serum B12 concentrations and vitamin B12 deficiency because the bacteria utilize vitamin B12 for their own metabolism so B12 cannot be absorbed by the body

A 22-gauge, 1.5-inch needle is usually adequate to reach most superficial muscles

Not in newborns

Whats almost certainly NOT a B12 toxicity sign: bright yellow urine (thats B2), mild GI upset on the first dose (thats just a large pill), or feeling wired after taking a B-complex (thats more likely caffeine or other stimulants in your stack)

The exception to this rule is the single preparation of the sub-Q or IM dose that exceeds the volume safely injected at a single site