Sub q should in theory give close to 100% bioavailability, but we really dont know the one PK study never tested it, so theres no measured number and no dosing conversion behind it
For patients without absorption disorders, high-dose oral supplements of 1,000 to 2,000 mcg daily have been shown to be comparably effective at correcting mild to moderate deficiency at lower cost and greater convenience.
If your vitamin B12 deficiency is caused by a condition or medication that affects absorption, or your levels are very low, your GP may prescribe a course of vitamin B12 injections
Foods that are rich in vitamin B12 include milk, meat, and eggs
For individuals experiencing fatigue or low vitamin levels, B12 injections may help support normal energy levels before and during travel
Then, aliquot this stock solution into smaller, labeled microcentrifuge tubes