Avatar universal

Low FT3 and FT4, normal TSH

I’ve been suffering from Hashimoto’s for the past 8 years and I’ve been on desiccated thyroid for the past 6 months or so. My doctor and I are still trying to find the right dose. I'm currently on 30 mg.

I recently got my test results and both my FT3 and FT4 are low. What’s strange is that my TSH is low-normal. Has anyone else had this happen?

My TPO has practically doubled over the past month and my TG went from positive to negative. I’m really confused about what’s going on with my body.

Here are my test results:

February 2019:
TG: <20 (Ref < 40) <- this antibody came back positive in January and negative in August
TPO: 770 H (Ref <40) This antibody always comes back high

TSH: 0.5 (ref 0.35-5.0)
FT3: 3.2 L (ref 3.4-6)
FT4: 11 L (ref 12-22)

January 2019:
TPO: 380 H (<40)
TG: 130 H (<40) <- this antibody was negative in August

TSH: 0.05 L (0.3-4.0)
FT3: 3.6 (2.5-5.9), bottom 32%
FT4: 14 (9-19) , right at 50%
6 Responses
Avatar universal
Update: upped to 60 mg desiccated thyroid
Avatar universal
When did you increase to 60 mg?  What symptoms do you have?
My dose was increased earlier today.

I recently gained 10 lbs in 1 month eating less than I normally do.
Severe memory issues - very frustrating and noticeable. Sometimes I feel like I'm losing chunks of time. Some of my friends are concerned.
Very dry (nearly scaly skin). Could be because of the winter.
Surprisingly I look healthy.
Avatar universal
One of the best definitions I have seen for hypothyroidism is "the clinical state of suboptimal T3 effect in some or all tissue in the body".  So it should not be a mystery why you are having hypothyroid symptoms.   Your FT4 and FT3 are at rock bottom of ranges that are already far too broad, due to the erroneous assumptions used in establishing those reference ranges.  Just being anywhere within the so-called "normal" range does not mean results would be optimal for you.  Plus there are many other variables that affect the RESPONSE to thyroid hormone at the cellular level.  There are numerous studies that show even in the untreated state TSH has only a weak correlation with FT4 or FT3, and a negligible correlation with symptoms (TISSUE T3 EFFECT).  Also, FT4 and FT3 have only a weak correlation with symptoms.   So, there are no reliable direct measures of a person's TISSUE T3 EFFECT, which determines thyroid status.    The best indirect measures of your thyroid status are an evaluation for symptoms that occur more frequently with hypothyroidism, supported by tests for Free T4 and Free T3.  

In the treated state,  studies have shown that many patients taking thyroid hormone  will have suppressed TSH levels.  Studies have also shown this to be a result of taking the full dose of thyroid hormone only once or twice daily, which establishes an equilibrium among TSH, FT4, and FT3 that is quite different from that with the usual continuous low flow of natural thyroid hormone in the untreated state.  So, a TSH test is even less diagnostic in the treated state.  TSH-deficiency has no pathological effects.  A suppressed TSH in a treated person does not indicate hyperthyroidism and the need to reduce med dosage unless there are attendant hyperthyroid  symptoms due to excessive serum levels of FT4 and FT3.  So TSH should not be used to determine thyroid hormone dosage.   Instead the patient should be treated clinically, to relieve hypothyroid symptoms, and to optimize other important areas such as cortisol, Vitamin D, B12, ferritin, and Reverse T3 (if initially found to be excessive).  

So it is good that your doctor increased your dosage.   Most hypothyroid patients taking NDT (desiccated) thyroid med need between 2 and 3 grains (120 to 180 mg) in order to relieve hypo symptoms.   The final amount should be determined by relief of symptoms.   At your age, you should try to get an increase every couple of weeks up to 1 1/2 to 2 grains, dependent on body weight.  Then after 8 weeks, further increases should be determined by a re-evaluation for symptoms and tests for FT4, FT3 and TSH.  

Regarding your question about changes in FT4 and FT3 level,  do you take your thyroid med in the morning before blood draw for tests?
Thank you gimel. I didn't take the medication the morning of the tests (I waited 26 hours).  My FT3 and FT4 are outside the reference range at this point.
Avatar universal
Have you had any additional dose increases?  Have you been tested for Vitamin D, B12 and ferritin?
My dose was upped from 30 mg (once a day) to 60 mg (30 mg twice a day) last week. I still feel like crap but hopefully it'll start working soon.

My B12 levels are always on close to the high end of the normal range.

My vitamin D level is generally low-normal. It hasn't been checked in a while but I'm using a cream supplement (10000 IU cream, the highest possible dose).

My ferritin level was 30 (ref range: 10-105) when it was checked a couple of weeks ago. I started taking an iron supplement a 3-4 weeks ago.
Avatar universal
I expect that you are going to need a number of increases yet.  Most people seem to need to take 2-3 grains (120-180 mg) to achieve symptom relief.  So I suggest that you should try to get back in to see the doctor, get new tests and a dose increase as soon as you can.  Your serum T4/T3 levels will reflect over  95% of the total effect of the med increase in about 5 weeks, so a month from now would be a good target for the next appointment.  
Thank you Gimel. I have a follow up appointment with her in 3-4 weeks.
B12 serum, depending on ur range should be on high side. If 5-600 consider it low. Ferretin should be 70-90.

I had mine tested and that was info given to me. I am having full T3/T4/RT3 with TPO and TAA. I should have results by end of week. Since my diet is terrible, I have inflamation issues, my RT3 may be high. I am on 90/Armour. I am feeling better with VitD/B12/Iron/digestive probiotic/digestive enzyme/ magnesium threonate and folic acid supplementation. I am getting DHEA and Cortisol tested too. I am trying to treat underlying issues as well as hishimotos.
I've tried all the above (except for B12 because it's always close to the high end of the healthy range). I'm currently taking an iron supplement so hopefully my levels will improve overtime.
Avatar universal
From "Diagnosis and Treatment of Hypothyroidism: A Patient's Perspective, ref. 104 on iron deficiency (ID),which is the most common and widespread nutritional disorder in the world.

It appears that for the diagnosis of ID, a cutoff of 100 μg/L for serum ferritin concentration should be considered in most conditions and 20% for TSAT, except in particular situations, including young healthy women with heavy menstrual flow. New indications of intravenous iron supplementation are emerging."

Thank you Gimel
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