Pernicious Anaemia Society
15,941 members11,166 posts


Hi I am writing to see if someone can help me understand something? When I was about 29 years of age I had to have colon surgery for the removal of almost all of my intestine. The doctor said that they only left me enough to keep from having to have a colostomy. I was told that I would have to take B 12 injections for the rest of my life, which I have done up until a couple years ago, due to the expense I could not afford to take the injections. Now my doctor has started giving me my injections once a week and I just had my blood test done which says that it was marked at 2000 PG/ML but yet it was marked as low, my doctor seems confused at this point so what do I do? My doctor says that the 2000 PG/ML means that it is high but the results of the test say it is low, can anybody give me a little insight into how this could be? Thank you in advance for any information that you could give me!

7 Replies

I wouldn't be too concerned as test results are invariably skewed when receiving injections ..... it only tells you what is circulating in the blood and not the amount reaching the cells - where it is needed. Symptoms ? - do you still have any ?

1 like

Yes, I am still having severe fatigue & tingling & cramping in my legs, feet & hands. I'm also having more nausea than usual & itching all over! The itching is driving me crazy!


You do have a great deal on your plate - having read your Profile. I have read that symptoms often become worse before they get better - so I would persevere with the regular injections. Are you taking Folic Acid with the B12 injections ?


Somebody has made a mistake.

2000 pg/ml is probably the top limit of the assay used, which means that your B12 level is very high. Which is exactly what would be expected if you're receiving injections once a week.

The doctor should contact the test lab and ask them to clarify.

1 like

I've been getting injections once a week for a couple of months & my symptoms are worse now, especially fatigue, nausea & itching! I thought the measuring was somehow different? The dr that is giving me the injections is puzzled! He did not do blood testing levels prior to starting injections!


2000 is likely to be the top of the measurable range. This is what would be expected if you had had a 1mg shot in the last 7 days

Assuming that you aren't UK based from description of treatment.

Are the injections methylcobalamin or another form of cobalamin? People can respond differently to different forms of B12 and methyl doesn't necessarily suit everyone - so that is one thing your doctor could look at.

If you are one month in then it is still very early days - particularly if you had signs of macrocytosis.

if your ileum was damaged by the colonoscopy then you won't be able to absorb B12 from your food anymore which is why you were told that you would need shots for life. Presumably you were symptomatic of B12 deficiency before you started on the shots so in the circumstances there wouldn't really have been any need for establishing your levels.

if things go on and switching to a different type of cobalamin doesn't do anything then suggest that your doctor looks into functional deficiency (run MMA/homocysteine and see if levels are still elevated). More frequent shots are likely to be needed if you are having functional deficiency (a response to the raised levels of B12 in your blood).


No, I take flaxseed oil, probiotics, multi vitamins, & prescriptions for high blood pressure (metoprolol) neurontin for neuropathy phenergan for nausea, & pain medicine. I use latanoprost for glaucoma, restasis for dry eyes, & lasix.


You may also like...