B12 injections one or two needles?

Hi all

Just be told I have very low b 12 and given a prescription for b12 it comes in glass ampules and I have to self administer . I was given some blue needles also. Just wondering if I'm doing it right ? As I looked it up on YouTube and some people use two needles and some just the one?

I just draw up with one blue and give . Then I read something about glass shards so now I'm freaking out that I injected myself with glass shards ? What are your thoughts?

31 Replies

  • The main reason I use two needles is that it's easy to rub the point on the bottom of the vial, thus blunting the needle and making the injection more painful.

  • Oh I see I don't think I have done that ...but I'm afraid about the glass shards now...😕 Have you ever heard of this being an issue?

  • My nurse explained about the possibility of glass when i ask why she used two needles.

    I think for peace of mind in future you could use two, but i wouldnt panic about it. I have had glass in my knee after an accident for 40 years with no effect except when a bit 'erupted' and came out.

  • Thanks for your reply.. Yeah I guess even if I did inject glass by accident it would be that small the there wouldn't be any damage...

    It's funny as I had my first dose in the surgery & burse drew up with blue & gave with blue never changed needles ... Suppose everyone works differently .. I would love to know what's right.

    In future I'll use two to be safe!

  • Does your nurse draw up with a blue needle? Or did she use a filter needle ?

  • Dr where I work taught me to draw up on a yellow 20g, then change to an orange 25g. 1 or 1 1/2 " . before administering. One of the reasons for changing needles is that if you get any of the b12 serum on the needle you inject with, it l tends to sting. I've been self administering this way for 20 years and no problems whatsoever.

  • I use two needles, blue 23Gx1" for injection and green 21Gx1.5" for drawing up as I found that the point can get quite bent / blunt against the bottom of the ampoule - I don't want to miss any!! :-D

    Also the 1 inch ones seems to be the right depth for my injections but are a bit short to easily reach the bottom of the ampoules.

    I hadn't heard about the glass shards or filter needles until a few days ago despite having done animal injections for 20+ years so I'm not worried about it.

  • Thank you so much guys for your replys

    Denise that's great I shall order some green 21 g right now and use them to draw up and the blue to give .

    Can I ask if the Doctor adviced you on this method to administer ie green to draw up and blue to give?

    I know I freaked when I read about glass shards but a lot of people don't seem concerned so now I have peace of mind about it.

  • I just use one 30mm (1.25 inch) 23g needle. Changing the needle isn't going to prevent small glass particles, if there are any, being injected unless the first needle is a filter needle.

  • Changing the needle is done primarily to maintain sterility.

  • This is very true and makes logical sense however I'll get some green 21 g drawing up ones just incase I blunt it on the glass ample!

    Thanks for your reply :)

  • My nurse uses a green to draw up and a blue to inject, and she said that she was told that even a slightly blunt needle is more painful. As that is what she does I decided I would do the same.

    I have noticed that the NHS vials are well-scored, so the tops snap off cleanly. The stuff I got from Germany isn't, and the first few shattered, rather than snapping. Now I use one of these - sepha.com/en/products/view/... - to score and snap the vial.

  • Thank you Fbirder.

    Oh really that's sounds a bit dodge can you not get any more NHS ones or are they cheaper from Germany.

    I'll look into that link thank you :)

  • I've used three different brands of hydroxo fron Germany (Hevert, Lophacomp & Rotexmedica) and have never had a problem snapping the top off the ampoules using the method I was shown by the nurse at my surgery. I make a vertical fist with my right hand, pop the ampoule into the hole formed by my first finger so it is supported but not held tightly and snap the top off with the thumb and first finger of my left hand quickly and firmly. It's difficult to describe but easy to do once you've worked it out. I've opened more than 200 like that without breaking one.

  • Maybe I had a duff batch of Hevert. I've got some more, so I'll try one of them next week.

    When I was working I regularly had to open ampoules of various chemicals. I must have done over a thousand.

  • I bought some from Germany when I first started self-injecting, before I knew just how nice my GP is. He's prescribed it for weekly jabs, so I have a ready supply of the NHS stuff.

  • Possibly the best way to avoid blunting the needle is to turn the ampoule upside down after snapping off the top and then, if you have a steady hand, you can just insert the tip of the needle into the liquid to draw it into the syringe without the needle touching the glass at all.

  • Surely needles would block if there were glass shards in the fluid? Any thoughts?

  • I use a pink to draw up the fluid because the lumen is wider and then a green to administer the injection. The green needle is used for an IM injection but blue can also be used especially for thinner people.

    No one should self inject unless instructed by a healthcare profi on how to do so safely, for example selecting the injection site (rotating the site), how to use and choose the equipment and how to inject. If you are in any doubt, speak to your doctor or nurse. Nerve damage can be caused if you make a mistake so please get some instruction and build your skills and confidence.

  • Hi Granny56

    Thank you for your reply .

    Can I ask you about the pink needles you use to draw up from the glass ampules?

    Are the pink needles a 18gauge and are they filtered or non filtered.

    And we're they recommended by your doctor / nurse to use?

  • The pink needles are 18g unfiltered. I have been using this method for 30 years, a method I was taught in my nurse training many years ago. Perhaps new techniques are available now such as using filtered needles. However, if you are careful these extra safety measures in my opinion are not needed.

    I break the ampule open, draw up the fluid with 18g being careful not to touch the bottom of the ampule, which is a large bore needle for quicker drawing up ( you can also use a green one). I then change to a green 25g needle which is slim and long enough to penetrate the muscle. A blue needle will only do this in very thin people.

    If any minute glass particles exist from breaking open the ampule, a filter might be a good idea however, 30 years without a filter has not done me any harm.

  • Your advice on needle colours makes no sense. Under the standard needle colour coding scheme, green needles are 21g not 25g. 25g needles are orange, 23g are blue and 21g are green.

    All needles are available in a number of different lengths so it is not sufficient just to select needles by gauge/colour.

  • I did not give advice on needle colours, I merely documented my own routine, therefore I find your over reaction a little offensive. I made an unintentional mistake writing the gauge size for the green needle, of course its 21g and not 25g...please excuse me for being human. bd.com/resource.aspx?IDX=11201

    The advice I did give if you read my earlier post was to check with your local Dr or nurse if you are in any doubt about equiptment or how to use it.

  • Thank you Granny56 for your advice I appreciate. :)

    I guess whe your drawing up with an 18g and then changing the needle to a 23g any glass shards which may (by the off chance) been drawn up by the 18g would not get through a 23g needle anyway if that makes sense. Would you agree?

  • Thank you Jessica, yes that is correct however, there is always the possibility of tiny wee glass particles being present. If you see any glass particles, then discard the ampule and start again. The manufacturers of the ampules have improved over the years so normally a clean snap can be achieved if you look for the small line on the glass and snap the top of from there.

  • Thank you so much Granny56 😊

    I'll take that advice on board.

  • Granny56 can I ask what the implications would be if a tiny glass shard you didn't see was injected? Would it be a big deal?

  • I spent about 10 years with a small fragment of glass in my finger (shattered a pipette puttin git in the pump). I didn't even know it was there until it started getting near the surface.

  • Hi Jessica,

    I answered this post but can't seem to see it. Anyway, what I basically said was probably no harm would be caused if it it not visable to the naked eye. i am sure that I have injected a few minute particles of glass over the years and I am still here to tell the tale.

    The only other warning I would give is to ensure you know and understand your injection sites. Ask your local nurse to go over them again with you so that you are not in any doubt.

    Festive Greetings


  • Hi Granny 56

    Thank you!

    I will be sure to check for any visible glass shards before injecting.

    Merry Christmas 😊

  • Hi everyone!

    I'm new to this form.

    Granny56 I see your a nurse so I'm keen to get your advice if you wouldn't mind!

    I have been injecting b12 for the last 6 months and use the same method as you I use a 18g to draw up & blue to administer!!

    I was never told to look out for any glass shards by the nurse or doctor and never thought about it until I saw this post.

    so possibly there may have been visible glass shards which I injected over the months and never noticed( as I wasn't really looking our for them) low & behold I'm here to tell the tale!!but could it cause any long term effects ( if perhaps there was visible glass shards that I didn't see as I wasn't looking) in the future?

    What do you think? Or am I fine and worrying over nothing!

    In future I will be sure to look out for them!

    Thanks in advance!

You may also like...