Tests after Biotin stopped

[vocalEK]

SlowDragon suggested I put up a post of my own, so here goes. I have been bugging my PCP for nearly two years about my lingering symptoms of hypothyroidism, despite being on 175 mcg / day of Synthroid. Specifically, going bald, fragile nails, cold intolerance, dry gritty eyes, difficulty losing weight, puffiness under eyes, and fatigue. There's more, but these are the ones that bother me most. Doctor had a boatload of tests done to rule out causes other than hypothyroidism, including 24-hour urine collection, female sex hormones, male sex hormones, C-reactive Protein, ANTINUCLEAR ANTIBODY, RHEUMATOID FACTOR TITER, DOUBLE STRANDED DNA ANTIBODY, SJOGREN SYNDROME A ANTIBODY (SS-A) AND SJOGREN SYNDROME B ANTIBODY (SS-B)

. All were "normal". I was told the same thing about my thyroid tests, but then I stumbled across the information that taking biotin can screw up the results you see on lab tests. So I went off all vitamins (just to be sure) and asked the doctor to retest. I sent her a link to this: sciencedaily.com/releases/2...

I did notice a difference after going off Biotin. She wrote that T3 was little low, and we should retest again after 6 weeks.

[SlowDragon Administrator]

Do you have Hashimoto's? If not had TPO and TG antibodies tested you need these done

Also ferritin needs testing

Are you on strictly gluten free diet?

Your TSH is rising, so you may have room for dose increase

Or look at adding small dose of T3

Your FT3 is obviously too low

Post your next test results when you get them

[mado]

I am really sorry but I read the article and I still don’t understand what biotin has to do with any of it. I take biotin regularly when I eat protein because otherwise I have a lot of food sensitivities and I cough all the time

[helvella Administrator in reply to mado]

Some laboratory measurements are affected by biotin.

If you take a biotin supplement it might affect TSH, FT4 and FT3 tests. The results might be higher or lower than would otherwise have been the case.

This affect on test results could mean that your treatment is mis-managed.

Not all TSH, FT4 and FT3 tests are affected. Many are not affected.

Ordinary dietary biotin does not affect tests. Medium to high doses of biotin can have these affects.

For ordinary biotin supplements, stop taking a few days before your blood is drawn.

Last I checked, there was inadequate evidence as to how long you need to stop taking them before blood draw. Maybe a week?

You could ask the lab that does your blood tests whether their testing procedures are affected by biotin.

[dinahnow in reply to helvella]

This happened to me. I take daily all-vit.B's supplement. Did test with Thriva, then read here about biotin effect on results. Contacted Thriva - they do use biotin, and they sent a fresh test and re-tested for free, agreeing they need to put this in their instructions.

[SlowDragon Administrator in reply to mado]

mado

Cough is often caused by acid reflux or dairy intolerance

Acid reflux is often low stomach acid due to being under medicated and still hypo

What are your most recent blood test results and ranges for thyroid and vitamins

Are you on dairy free diet?

[mado in reply to SlowDragon]

Aww thanks but I only wanted to know how biotin affects results and it’s been answered. My coughing has nearly stopped now that I take biotin and yes I am dairy and gluten free. Thanks

[Carrob]

Biotin also falsely lowers parathyroid hormone

[helvella Administrator in reply to Carrob]

Does it lower the actual parathyroid hormone (PTH)? Or it affects the test for PTH?

[MaisieGray in reply to helvella]

"........ The role of biotin interference was confirmed in one of the patients when she was retested off biotin, and PTH levels responded appropriately. Biotin supplements remain as unbound molecules in the serum, thus interfering with PTH enzyme-linked immunosorbent assay (ELISA) results and falsely depressing the PTH level." Waghray et al

[Angel_of_the_North]

I think the problem is that you are not converting t4 to T3 - your free t4 is almost at the top of the range but your free T3 is under range - doesn't look as though your lab was using an assay method that is affected by biotin. " T3 was little low". No, it's not even in range and needs to be near the top of the range! You needed T3 added to your levo

[MaisieGray]

"She wrote that T3 was little low"

In fact your first test showed T4 high in range and T3 below bottom of range; whilst your third test showed T4 above range with T3 more or less bottom of range. Those results appear to indicate adequate medication but that you aren't converting T4 to T3 adequately.