Timing blood tests for folate/B12

[fluffyhat]

Sorry for asking what must be a common question..Do you need to stop folate 2 days before testing?

Is it 2 or 4 months for B 12 please?

Thank you

[jade_s]

I'm not sure we have any guideline for folate but would like to see what others say.

You should avoid any supplements with biotin minimum 3 days, such as in a B complex. And 7 days if on high dose Biotin. It interferes with quite a few of the test assays.

B12.... well if on injections, it shouldn't be tested except in certain situations & with a knowledgable doctor.

If on tablets, and you've been on high doses, and you're trying to prove malabsorption, then 4 to 6 months. However, intermediate testing may show large drops. B12 testing is sometimes an art.

And if you suspect pernicious anemia or other malabsorption issue, then there are other tests that can & should be done.

If you share more of your story - have you been supplementing & how much, historic b12 levels with and without supplements, symptoms especially any neurological ones, it would be easier to give guidance.

[fluffyhat in reply to jade_s]

Thank you!Yes, will post more details..basically never supplemented..

Neuro symptoms, hypothyroid, gluten intolerant...

Sl. In shock as GP agreed to 6 loading doses injections after I posted...says can only have 6 , if improvement can have tablets...will cross that bridge in 2 weeks...will share more details at weekend. 😊

[jade_s in reply to fluffyhat]

Well that's a great start!

I would push for as much testing as you can get now, to get a baseline. Tests i would get:

Intrinsic factor antibody test

Gastric parietal cell antibody

Homocysteine

Serum B12

Folate

If nothing else, the antibodies, b12, & folate tests, assuming they haven't been done recently.