Update - Blood work after taking Cytomel (T3) - Thyroid UK

Thyroid UK

137,933 members161,759 posts

Update - Blood work after taking Cytomel (T3)

vocalEK profile image
9 Replies

After years and years on generic levothyroxine and years and years of hypo symptoms getting worse and worse, I put together a list of symptoms and asked my new (young) Primary Care Provider (a general practitioner) last year for treatment to correct at least some of these. She tested TSH and FT4 and also did a bunch of other tests to rule out other possible causes of these symptoms. I finally convinced her to test free T3 as well and also vitamins and antibodies. My Vitamin D was tested by a podiatrist in October 2017 and found to be low. Consequently I began supplementing then. D has come up since then, but perhaps not high enough (?) I've just switched to the combo of D&K recommended in this community. I am also taking B complex, magnesium, selenium, and zinc.

After my PCP found free T3 "a little low" in October and even lower in December, she agreed to give me a trial of Cytomel (T3). I titrated dosage slowly, as she had prescribed 25 mcg. So I started out on 1/4 tablet per day, doubling the dosage every two weeks until I worked my way up to a full tab. My latest blood work shows the FT3 finally within range, although I would like to see it in at least the upper half. I should mention that the lab changed its standard range for FT3 between October and December of 2018. Hence the two ranges noted, with an asterisk next to the latest one, as well as the values that used that range.

My PCP has prescribed another 30 days worth and we shall see where it goes from here. NOTE: Be sure to review the suggested tags from HealthUnlocked. It wanted to add Phencyclidine. I removed it because my doctor is not an illegal drug. ;-)

Written by
vocalEK profile image
vocalEK
To view profiles and participate in discussions please or .
Read more about...
9 Replies
SlowDragon profile image
SlowDragonAdministrator

Do you feel noticeable improvement since T3 added?

How do you take it?

As split dose or all in one go?

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and fasting. Last Levothyroxine dose should be 24 hours prior to test, (taking delayed dose immediately after blood draw). This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)

If/when also on T3, make sure to take last dose 8-12 hours prior to test

Is this how you do your tests?

Presumably you know to stop b complex or any biotin supplementing a week before testing as biotin can falsely affect test results ?

Perhaps retest vitamin D soon too

vocalEK profile image
vocalEK in reply to SlowDragon

At the time of the test I was taking both hormones in the mornings. I intended to cut the T3 tab in half the day before and take the 2nd half around 8 p.m. (which would be ~12 hours before the test), but I forgot. So T3 may actually be higher than the test showed. I knew about biotin. I have decided to split up the dose of T3 from here on out.

As for improvement, another fly in the ointment (or wrench in the works, not sure of the UK phrase), is that I have been fighting an infection in either my teeth or sinuses (swelling in upper gum above back molars that extends up into my cheek) and was taking metronidazole at the time.

Recall that my ferritin level in December had been over range (185.5 ng/mL [10.0 - 150.0 ng/mL]), despite normal iron panel, which can indicate inflammation. After 6 days or so at 250 mg metronidazole, followed by 10 days of 500 mg 3 X day, the swelling has gone down considerably, but there is still a little residual. I will take it up with my dentist when I see him again next Friday.

Nevertheless, the chronic constipation has turned into regularity, and my thin straw-dry hair has become oily if I go for more than 2 days without washing. I still really need my afternoon nap and nails are still brittle and splitting. Yet it takes quite a while for hair and nails to renew themselves, no?

SlowDragon profile image
SlowDragonAdministrator in reply to vocalEK

So it sounds like you're definitely going in the right direction

Personally I find I can only take my T3 as 3 split doses. (Here in UK it's 20mcg tablet) 1/2 tablet on waking. 1/4 tablet 3pm and 1/4 tablet at bedtime (so each dose is 8 hours apart)

Late dose at bedtime can help improve sleep.

Others find twice a day 12 hours apart works fine

Even if you do normally take it all in one go, ideally on day before bloods, best to split dose, and last dose 8-12 hours before test

So yes your FT3 is likely not as low as test shows

Yes, nails can take ages to improve

My ferritin is also always slightly over range. Seems relatively common problem.....perhaps due to inflammation?

Vitamin D might be better a bit higher. Getting out in the sunshine perhaps, if you have any!

Here we use "fly in the ointment".

Not heard "wrench in the works"

LAHs profile image
LAHs in reply to SlowDragon

It's "Spanner in the works."

vocalEK profile image
vocalEK in reply to LAHs

:-) merriam-webster.com/diction...

LAHs profile image
LAHs in reply to vocalEK

The English for "Wrench" is "Spanner".

vocalEK profile image
vocalEK in reply to LAHs

But then there is this one: dictionary.cambridge.org/us...

vocalEK profile image
vocalEK in reply to LAHs

When I googled the origin of the idiom, Quora responded:

Its history is apparently related to the "Luddites", a labor movement that sprang up in Britain in the early 1800s to protest the effect that industrialization was having on living and working conditions. Protesters would literally "throw spanners into the works" to damage or destroy industrial machinery.

Asmm2766 profile image
Asmm2766

I didn’t hear that your doctor had tested your reverse T3. Levothyroxine is a T4 medicine and it can cause in some people to make large doses of reverse T3 which then fill up the T3 receptors. Both numbers can be in the normal range, but if the ratio between the two is off, you can feel quit bad. I felt so bad that my prayer was, “God, fix me or take me. Either one’s OK… I can’t live like this.”

If the ratio is off, your cells aren’t getting the free T3 which is what it needs. If you read my bio, I go more into depth of my experience and where you can find the knowledge you need to make informed decisions and find a knowledgeable doctor. Good luck! Keep doing the research and advocating for yourself. There is hope. I am walking proof.

You may also like...

Testing after taking new Cytomel / T3

more quickly, would it be okay to get blood levels tested after 2 weeks of adding T3? Is that...

Lower T4,T3,FT3,FT4,TSH after taking Levo

6.64 (range 5.10-14.10) FT3: 4.50 (range 3.10-6.80) FT4: 14.80 (range 12.00-22.00) TSH: 1.35

after taking 50mg levo here are my bloods after a month

of my symptoms but here are my bloods: Vitamin D (25 Hydroxy) - Final - 06/05/2021 05:07 Vitamin D...

T3, cytomel and weight issues

the test to be done but she won't refer me as she's worried that they'll prescribe the T3 cytomel...

Help with normal blood ranges when taking T3

About a year ago I switched to T3 and my doctor is concerned that my thyroid function blood test...