Hello mountainpass,

I have already replied separately to your PM of the same subject. As promised, here is a more detailed response.

To make it easier to follow this, I will make a summary of what you have told us, regarding your B12 problem; I am assuming that your units for serum B12 are ng/L (= pg/ml). Please let us know if I have made any error:

• 30 January 2008: Test - Serum B12 = 507 ng/L (= 374 pmol/L)
• ?? March 2008: Test - Serum B12 = 353 ng/L (= 260 pmol/L)
• ?? March or April 2008: Commenced B12 Treatment - 1 x 1000 µg/day methylcobalamin for 2 weeks
• ?? April 2008: Increased B12 dose to 2 x 1000 µg/day methylcobalamin for 1 week - horrible, horrible worse headache
• ?? April 2008: Increased B12 dose to 5 x 1000 µg/day methylcobalamin for 1 day - headache and put to sleep
• Late April 2008: One cyanocobalamin injection - huge headache
• Early May 2008: Commenced 1 x 1000 µg/day Jarrows methylcobalamin

I shall consider separately the three issues of cause, diagnosis and treatment:

1. Cause

There are many possible causes of vitamin B12 deficiency; hopefully by now you will have read about these already. You can find this information on the forums and elsewhere on the www, including my web site.

One possible cause is bacterial overgrowth of the small intestine. This could prevent absorption of the B12 from your food; it might even prevent absorption from oral B12 supplements.

One way to get this bacterial overgrowth is to take antibiotics. These often kill the beneficial bacteria in your intestines, leaving to harmful ones to take over. This is why patients are sometimes advised to take doses of "good bacteria", such as acidophilus, after finishing a course of antibiotics.

It is possible that the Tequin has killed off your good bugs, leaving you with an overgrowth of the bad ones, thereby causing your B12 deficiency.

I suggest that you discuss this possibility with your doctor. Perhaps he/she will refer you to a gastroenterologist for an investigation.


2. Diagnosis

As I have explained in detail, on my web site, serum B12 is not useful as an indicator of vitamin B12 deficiency. It is potentially useful as an indicator of your B12 body stores, but only if you have ceased treatment for several weeks before the test.

I note that your reported serum B12 level fell significantly early this year. If you were not taking any supplements at that time, the fall in serum B12 level does indicate a severe depletion of your body store in a very short time. This suggests that something is interfering with the recycling of the B12 in your body.

Unfortunately, you appear not to have had a test for methylmalonic acid before taking supplements. For reasons that I have given in detail on my web site, you cannot now use MMA for diagnosis because you do not have a valid "before" result. You can still use MMA to monitor treatment.

Please see my post #27 on this thread for an explanation:

http://neurotalk.psychcentral.com/thread43009-3.html


3. Treatment

My impression is that you have not understood how the oral B12 treatment works, and therefore perhaps have expected too much too soon.

The purposes in taking high-dose B12 are:

• Quickly reverse the deficiency - ensure that B12 is available to cells for metabolism and minimise risk of irreversible harm
• Build up your body stores - ensure that there is no depletion in future

Even if a person cannot absorb any oral B12 normally, they can usually absorb about 1% of any dose. This is possible because of a process called "passive diffusion". This means that, unless you have a particularly unusual problem, you should absorb about 10 µg of each of your 1000 µg doses of methylcobalamin. It will therefore take about 200 to 300 days to completely fill your body store with the normal supply of 2 to 3 mg B12.

This is not how long it will take to reverse the deficiency. Your metabolic markers, indicating cellular deficiency, should return to normal within a few weeks of commencing mega-doses of B12. It can, however, take many months or years for your nerves to recover, so you need to be very patient.

You could take 1000 µg twice each day; one before breakfast and one before your evening meal. This should fill your body store in 100 to 150 days. Another alternative is to have a series of B12 injections, called loading doses. These are typically given as 7 injections of 1000 µg over a two week period. I have explained more about B12 treatment on my web site.

Because you had a bad reaction to more than the initial dose of 1 x 1000 µg/day, I suggest that you stay on the Jarrows 1 x 1000 µg/day. This should be sufficient to reverse your B12 deficiency, as well as gradually build up your body store.

I do need to offer a caution about oral treatment. I said above that "unless you have a particularly unusual problem, you should absorb about 10 µg of each of your 1000 µg doses". If you do have a bacterial overgrowth of the small intestine, you might not absorb any B12, even by passive diffusion. This is why it is very important to monitor the response to treatment.

You also need to know that you are not alone in your experience with unpleasant effects after taking B12 treatment; there have been many reports of this on the forums. I had very worrying symptoms after I commenced my 2 x 1000 µg/day cyanocobalamin, after I discovered my B12 deficiency in 2005. For a while, I was worse that before I was before commencing treatment. This was possibly caused by hypokalaemia, a deficiency of potassium. Mrsd has explained this potential problem to you in her post.

You should continue to monitor your treatment, to ensure that you are actually absorbing the oral B12. I note that you have just had a test for MMA and homocysteine; these are the best available tests for cellular deficiency. If these are normal, then this indicates any deficiency has been reversed, and your metabolism is returning to normal. You might still feel absolutely rotten for a while, but at least you have the B12 problem under control.


I suggest that you do the following:

1. Continue with the methylcobalamin 1 x 1000 µg/day

2. Discuss with your doctor the possibility of bacterial overgrowth of your small intestine as a potential cause of B12 deficiency.

3. Ask your doctor to order new tests for methylmalonic acid and homocysteine, after you have been on treatment for at least another three weeks, if the results of your first tests are abnormally high.

Please let us know if you have any further questions.

Paul