1ml or 2ml

When I go for my 3 monthly jab I’ve noticed some months I get 1ml and sometimes I get 2mls? I self inject 1mls. Do I need 2mls?

[deniseinmilden]

Different pharmaceutical companies produce B12 in different strengths.

The important bit is what the dose of "active ingredient" is - in this case hydroxocobalamin - which is usually given in units of mass (basically weight) mcg/mg/g/kg, etc., and not the volume of liquid it is carried in.

Most ampoules are 1mg in 1ml but some are 1mg in 2ml and there are other options.

I'm guessing but I expect sometimes the NHS has the weaker strength ones and so they give you a 2ml dose to deliver the same 1mg amount of hydroxocobalamin as you would get in 1ml of the stronger ones.

See what your ampoules say on the packet. It's not the end of the world but you should be aiming to get a 1mg dose. If they come in single dose ampoules then you should be using the whole of the liquid in the ampoule for each dose