[kristenb]

#1017902

I had my first labs since on replacements. I am a little hyper so Dr is lowering my dose from 100 to 88. I was wondering though … does when you take meds effect labs? I took mine about hour and a half before.

[Krisann79]

#1061560

No it shouldn’t. It normally takes weeks for the true result to show.

For example: I got on a new dose. Was doing great. Then a few weeks later I had my levels tested around 3 weeks in because I was having problems. The levels said they were normal….. stayed on the dose. At week 6 I was hyper and bouncing off the walls! It’s supposed to take 6 weeks.

[Kimberly]

#1061561

Hello – Krisann is correct that it takes several weeks to get a good read on whether a dose is right for you. However, I’ve been getting regular labs done going on 4 years now, and my doctor’s office has *just* started stamping the lab slips with a note that says “no thyroid medication morning of labs”. Perhaps they have found that taking the meds can have *some* impact on lab results.

[snelsen]

#1061562

Well, I have a very curious mind, and am very interested in "Evidence based research.) I know many on this site have the same thoughts. So I would like to pursue more information about why Kimberly’s doc (or is it the lab, Kimberly?) has stamped this direction on the labs slip for thyroid labs. So now I want to know if this is a "standard of care, " and a change in practice.
Is this a lab decision, or a doctor decision? I have not heard of this before, and checked with my endo and several labs, and they have not heard of this.

There are so many variables that impact taking thyroid meds so that our labs are accurately reflected. Regarding taking thyroid hormone, the most important ones we need to do to have our Grave’s managed properly are:
-take on empty stomach
-with glass of water
-no supplements for 4 hours
-labs AT LEAST 6 weeks apart, 8-12 weeks even better.

Shirley

[Ski]

#1061563

I think there may well be a difference between taking ATDs before a blood test, and taking replacement hormone before a blood test. Kimberly’s on ATDs, and Kristen is talking about replacement.

[Kimberly]

#1061564

Actually, I’m wondering if it has more to do with the specific test being ordered. On the WebMD site, the section on testing of T3 and T4 says, "If you are taking thyroid medicines, tell your doctor when you took your last dose. Your doctor may instruct you to stop taking thyroid medicines temporarily before having this test.". There is no such warning in the section on TSH testing — which makes sense, as TSH is a lagging indicator.

I guess the bottom line is to check with your doctor. And once you get an answer, be consistent with taking the meds or not *every* time you have labs done.

[Author]

Posts