vitamin b12 injection how long does it last Dosage for Adults: Guidelines How Long Does A Vitamin

Intramuscular (IM) route of vitamin B12 administration: The sublingual (SL) route of vitamin B12 administration has been evaluated as an alternative route to oral and IM routes, especially in the case of vitamin B12 malabsorption

Mishra and Chan, 2016

If dietary sources are insufficient, however, a doctor may recommend supplementation through pills or injections, depending on the cause of the deficiency.

A Canadian study (published in JAMA) examined people with diabetic kidney disease who were given high doses of B12 and B6

Once the 28-day refrigerated-use window is included, that works out to three 80 mg vials at the low 1.6 mg dose, three at the standard 3.2 mg dose, or four at the elevated 4.8 mg dose