B!2 level clarification

Re: my previous question, I have had extensive testing done - schilling, biopsy, other gastro tests.  No pernicious anemia. It is malapbsortion which is why I receive monthly injections

Since B12 is not toxic, wouldn't it be better to have a higher level than one that is low normal or low?

More importantly to me is learning how much B12 is lost in one month.  Is it possible to have 800 after injection and 200 4 weeks later?

Hopefully you will have that info for me - I have been unable to find.

[Kevin Pho, MD]

There are adverse side effects to an elevated B12 level.  This can include the following:

Central nervous system: Headache (2% to 11%), anxiety, dizziness, pain, nervousness, hypoesthesia
  Dermatologic: Itching
  Gastrointestinal: Sore throat, nausea and vomiting, dyspepsia, diarrhea
  Neuromuscular & skeletal: Weakness (1% to 4%), back pain, arthritis, myalgia, paresthesia, abnormal gait
  Respiratory: Dyspnea, rhinitis

That is why it is necessary to monitor the levels.  

If malabsorption is the cause, then treatment should be considered to correct this.  There is no "set" amount of appropriate B12 loss - it can vary from person to person.  It may be possible to have a level decrease from 800 to 200 in 1 month depending on the type of malabsorption.  

You may want to discuss with a GI referral evaluating and correcting any malabsorptive disorders (i.e. celiac disease) or considering any rare hereditary disorders that can lead to B12 deficiency.

This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.

Kevin, M.D.
Medical Weblog:
kevinmd_b

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