Blood tests for vitamins ect.

[Beach bum]

My gastro specialist has asked me to get a load of blood tests done to check how my vitamin reserves (such as D) are doing as well as a few other things.
I am just wondering if I should hold off from taking my usual supliments for a bit before - and if so how long , so as not to give a false result , as it seems to be reserves she was interested in?

I ask as when I was first tested for anemea years ago the doc told me not to take any iron supliments before.

I am due to have my pre infliximab bloods done in a week or so.

 

[Beach bum]

http://www.crohnsforum.com/member.php?u=1

David you know a bit about vitamins and such I think,any advice ?

Thanks.

 

[teeny5]

My GI asked me to get some blood work done as well. I didn't even think about supplements affecting the tests...great question!

Mine also wanted my cholesterol checked...did yours only ask about vitamins?

 

[Catherine]

I know iron supplement can give a false high for ferritin.

My understanding is it only matters if you going to stop the supplements base on the test results.

EG if you get a high result and stop taking vitamin D for example. You would retest the vitamin D in a couple to make sure your able to maintain the level without supplements.

 

[David]

A good question but I'm afraid I don't know the answer either. Sorry

 

[chuckmya]

I thought I read somewhere that you should stop taking vitamins/supplements 3 days prior to testing.....but I can't remember where I read it! Lol

 

[teeny5]

So... what does everyone do- keep taking vitamins and supplements up to the tests OR stop taking anything a few days prior???

 

[UnXmas]

I carry on taking everything. My doctor needs to know my medications are working and if increased supplementation is needed.

I think some work over the long term anyway. From the way my doctor talks about vitamin D for example, I get the impression that it's built up over months so a few days without supplements wouldn't make much difference. Or B 12. I'm having B 12 injections once every three months, so there's no way I could stop it for a test, and the injections must be working over a long period.

But it may be different for particular meds in particular circumstances, so ask your doctor.

 

[teeny5]

Ok so my Dr just wants me to fast 12hrs prior.