I have been self injecting B12 for the past 6 months previous to this I was taking 5 or 6 capsules throughout the day . The question I want to ask is now that I have totally stopped taking the capsules will the B12 level in my blood reduce as I have been injecting and it has increased my B12 level at a cellular level . I have tried to find out but I imagine the by injecting it also keeps your B12 serum level very high I was wondering if anyone can shed some light on this
B12 injections and sublingual b12 cap... - Pernicious Anaemi...
B12 injections and sublingual b12 capsules
injections are more efficient at raising your serum B12 levels just because much less is absorbed from the sublinguals especially if you have an absorption problem - and if you have an absorption problem it would be the difference between taking in 100% and taking in 1% (on average)
The amount of B12 removed from your blood by your kidneys gets greater when the amounts in your blood are very high. In general you lose about 50% of a 1000mcg shot in the first 24-48 hours. In the next 24-48 hours you will loose 50% of 50% = 25% etc. Those are averages and the 'half' lives will vary from individual to individual so it's difficult how long it will take for the levels in your blood to fall below the levels that you need.
Sally Pacholok recommends B12 supplements with injections, if that's any help.