What causes TSH yoyoing?

[scaredsilly91]

What causes TSH labs to change? I have been on the same dose of levothyroxine for three years and my thyroid went from 6 down to 2, up to 4 then down to 1, then up to 3 then down to 2, then up to 5 and down to 3. I know the levels of hormones in your body changes throughout the day, but my levels would steadily increase or decrease over the course of 6 months- for example, starting at 6, then to 4, then 3, then 2 and then turning around and climbing back up to 4.

My symptoms improved some but never really went away. I can always tell when my levels go up to the higher ranges and when they come back down but I've never understood why it happens or if it's a cause for concern.

Thank you!

[Red_Star]

Time of day tested:

The August 2012 study entitled "Clinical Significance of TSH Circadian Variability in Patients with Hypothyroidism" (Sviridonova MA, et. al) showed an average morning TSH level in the subclinically hypothyroid group was 5.83 mU/L and in the afternoon was 3.79 mU/L; 73% TSH circadian variability.  

The average morning TSH level in the hypothyroid group taking levothyroxine was 3.27 mU/L and in the afternoon was 2.18 mU/L; 64.7% TSH circadian variability.  Morning: 8 - 9 am. Afternoon: 2 - 4pm.

***

And an article that lists 15 other reasons...

About Guide - Reasons Why Your TSH May Be Fluctuating...

"Change in Dosage -- changing your thyroid medication may change your TSH.
Potency Fluctuations in your medication
Lab changes or mix-ups
The timing of when you take your pill
Starting or stopping a high-fiber diet
Starting/stopping calcium or iron supplements
Eating too many soy products
Eating too many goitrogenic foods, which include Brussels sprouts, rutabaga, turnips, kohlrabi, radishes, cauliflower, African cassava, millet, babassu (a palm-tree coconut fruit popular in Brazil and Africa) cabbage, and kale
Change of seasons -- TSH can rise in the colder months
Hormonal fluctuations
Pregnancy
Certain herbs/Supplements
Certain prescription drugs
Stress or illness
Progression of your thyroid disease."

[goolarra]

TSH is volatile and can change as much as 70% intraday. That's why it's a very poor indicator of thyroid status.

Your doctor should be testing FREE T3 and FREE T4 as well.

How do you feel?  Do you still have lingering symptoms?  Do you have Hashi's?